The canard of the papist with the divided loyalties—or, increasingly, any Christian as a matter of fact—is an old but persistent one, manifesting itself in the partisans of enlightened absolutism, the anticlericalism of the Risorgimento and the Kulturkampf, in American nativism, laicite, general secularist and republican opposition to "religious interference" in politics, the latter extending to the present and reaching its apex in the fedora-tipping antics of New Atheism, which at the same time is a movement that has its origins and greatest strength in countries that are historically quite anticlerical anyway.
It is not immediately obvious why the national state should be so hostile to "government of priests" as it was often pejoratively phrased, or to appeals to religious conscience when opposing certain legislation. The customary religion of the national group that the state is constitutionally formed to represent ought to matter, and hence a level of integralism and church-state symphonia should prevail. On the other hand, if the authorities see themselves as simply integrating an ethnolinguistic group and nothing more, then faith can be set aside. Yet most nation-states are liberal, and guarantee "freedom of religion." Despite liberalism once masquerading as a thin ideology, it was obvious to its opponents that it was a thick one and that its guarantees of religious liberty only extend to the point that religion is practiced in an insular, cloistered and literally autistic (as in self-centered) approach.
But why? Is it the paradox of tolerance? During the Kulturkampf, the Progressive deputy Eduard Windthorst in 1872 justified Jesuit expulsion by saying that "Germany is the land of the Reformation, the land of free science, the land of tolerance and enlightenment." Yet this cannot be the sole reason, since the application of any discriminatory standard entails "intolerance" of those discriminated against. There is no conflict between equal protection under the law, equality of rights and private discrimination, since the existence of intolerant groups does not compromise the independence of the legislature and judiciary to which all citizens are subject and equally dealt with.
On the other hand, the psychologist Adolf Zeising in 1873 had a more specific idea, proposing the following as a constitutional amendment for the Kaiserreich:
Only those who swear full, unconditional obedience to the laws and the constitutional authority of the state and who recognize no other authority over their actions, have a claim to the full enjoyment of state citizen rights [staatsburgerliche Rechte] namely the ability to hold public office and titles, as well as to vote in public affairs, to elect or be elected, or to exercise other political rights. Whoever, by invoking another authority, be it secular or spiritual, refuses this declaration or acts contrary to it forfeits his claim to these rights.
This is the principle of "you cannot serve two masters" taken to crushing conclusions. Actually it's a more specific claim, since it ultimately emanates from the idea of territorial monopolization of violence, as opposed to earlier divisions of concentric circles of justice, e.g. high, middle and low. As opposed to governing classes banding together in restrictive fraternities like ritterschaften and noble corporations, and as opposed to cities (themselves represented in the estates) forming protective leagues against encroachment by people otherwise invested with legitimate magistracy. Such traits are also exhibited in any form of confederal government.
Here, pastoral and episcopal hierarchies are a competing spiritual authority, rather than an organ in the body politick in their own right. Hence the Crefelder Zeitung in 1873 had an election manifesto with a call: "To your weapons, war comrades, against clerical rule, against Roman conquests!" The liberal considers expropriating priests to be warding off a coup. Foreigners and priests were made equivalent.
The spectre of a "black-red alliance" was a popular one in the later 19th century. The reasoning was that since both ultramontanism and communism were international tendencies having a bone to pick with the state, they were both essentially similar and would likely join forces. When your mind is haunted by a spook, the amount of spurious connections you can draw are without end.
No surprise that the attempted reconciliation by Liberal Catholicism, e.g. that of Lacordaire, Lamennais and Montalembert, was a fluke.
Of course, liberalism can never achieve the detached neutrality it seemingly aspires to. Not even in the sphere of foreign policy, with so-called non-intervention.
Julius Bachem (1845-1918), a jurist and one of the main intellectuals of the Catholic Centre Party (Zentrumspartei) in Germany, wrote in his pamphlet Die Sünden des Liberalismus im ersten Jahre des Neuen Deutschen Reichs (1872) about how unified Germany's initial proclamation of non-intervention by a Reichstag majority was already under fire in its first year by Bismarck's suggestion to intervene against the Paris Commune, and a now obscure naval incident involving the Prussian corvette SMS Nymph in Brazil. The point being that exigencies will always arise, and what is the state engaged in other than constant action?
It is said that in 1239 Henry III of England had remarked "I neither will nor dare to oppose the lord pope in anything." A far cry from the status quo centuries later, as besides the logically necessary anti-Catholicism of the Anglican church, England by the 1850s had committed itself to dismembering the Papal States and to dispense of the temporal power of the Roman Pontiff, in contradistinction to earlier views expressed e.g. by plenipotentiaries in the Congress of Vienna. This is documented in detail by C.T. McIntire in England Against the Papacy, 1858-1861 (1983).
The Illustrated London News in 1860 ran an article on Italian politics saying that "One thing is quite certain, and that is, that no possible settlement of the vexed affairs of Italy can take place while the temporal dominions of the Pontiff stand in its midst, a moral plague spot, at once contagious and infectious."
Conservatives and Liberals in England were in agreement that the States of the Church were an ineffectual priestly tyranny in contrast to England's exemplary model of civil and religious liberty, and that unification with/annexation by Piedmont under Victor Emmanuel and Count Cavour was the best option for the future of the papal dominions toward liberalism. The difference is that the conservative approach to foreign policy was more mellow, restrained and emphasized "reform," whereas the liberal approach was more openly radical.
James Harris, 3rd Earl of Malmesbury, had stated that "the dominions of the Pope are the most grievous sore of Italy, and that from that central point arises the principal heap of misery and just discontent." But far from simply advocating for papal reform, in a private letter to Lord Cowley he didn't rule out the possibility of "if necessary" employing naval power ("material assistance") "to establish another distribution by Catholic Powers of the Pope's Territory, or a forced improvement of the Pope's Government."
In doing so, Malmesbury undermined the previous English consensus since 1815 that the Papal States, though in some sense seen as backward, were a fixture of European politics whose territorial integrity ought to be maintained. Lord Castlereagh had supported Papal State restoration under Pius VII in the Congress of Vienna as a matter of course. England was also supportive of restoration in 1831 when revolution in Romagne flared up, and once more in 1848-9 when the Roman Republic was declared did England not object to French and Austrian intervention against it.
By the end of the Crimean War, things had noticeably changed, as McIntire narrates:
The two tendencies in the rising English consensus - against the papacy, and for Piedmont - conjoined in the Congress of Paris of 1856 when the powers of Europe met to settle the Crimean War. Cavour got next to Lord Clarendon, who was now British foreign secretary, and gave him a memo on Italy and against the Papal States written by the Marchese Gualterio in Rome. He played on Clarendon's attraction for Italy and dislike of the papal monarchy. In a forceful speech Clarendon went beyond simple reforms, called the papal government the most appalling on the peninsula and publicly proposed Cavour's suggestion of separate treatment for the Romagna. Palmerston brought the matter immediately to the attention of the English Parliament by claiming that 'the Holy City had not of late years been better governed than it was during the temporary absence of the Pope.' Both Palmerston and Clarendon were willing to consider armed coercion against the government of Naples and maybe even Rome to secure reforms. What they did was immediately to promote reforms by diplomacy through Richard Lyons in Rome, with the French joining in a year later. Both England and France anchored their naval fleets in the bay of Naples to scare King Ferdinand II, known as King Bomba, and then broke diplomatic relations with his government. Cavour tried to cement a bond with England by arranging the marriage of Victor Emmanuel with Princess Mary of Cambridge, a cousin of Queen Victoria, but failed when the princess declined to marry a Catholic. The English were actually a little wary of Cavour in the coming years, but the events in Paris put England squarely on Cavour's side, willing to accept Piedmont's dominance in Italy, and some kind of assault on the Papal States as the sore spot of Italy. For his war strategy, Cavour had to turn hereafter to Napoleon.
After 1859 with the Palmerston-Russell cabinet and the newly founded Liberal Party in power, annexation was vigorously published for, especially after the December 1859 appearance of a controversial pamphlet written by Arthur de La Gueronniere titled Le pape et le congrès advocating for a dismemberment of the Papal States, leaving only Rome and an area around the Latium, under the pretense of actually being the papacy's friend against conspiratorial elements ("Thus, then, the temporal power of the Pope is necessary and legitimate, but it is incompatible with a state of any size," La Gueronniere claimed). The pamphlet largely reflected the views of Napoleon III.
Émile Keller (1828-1909) was one of the big writers and practitioners of Social Catholicism during the fin-de-siecle alongside Louis Veuillot, Albert de Mun, René de La Tour du Pin, etc.
Keller's national and patriotic credentials are not in doubt, as when he supplied details on the bombing of Strasbourg during the Franco-Prussian War while deputy of Haut-Rhin, and later as representative in the National Assembly he protested the annexation of Alsace and Lorraine.
Earlier, in 1866, he wrote a book defending the Syllabus of Errors, translated into German as Kirche, Staat, und Freiheit. One chapter is devoted to Catholicism and nationality, a tense issue owing to the national idea's strong relationship to anticlericalism at the time.
Firstly, on issues of church-state relations, Keller actually believed that the situation had been improving since the time of Napoleon and his Organic Articles, which he described as:
From this point of view, where the schismatic tendencies are only the echo of the autocratic instincts, and where the idea of dominating the church was given only by the secret desire to start a universal monarchy, Napoleon I could not possibly stand. After suppressing the religious orders and confiscating the ecclesiastical properties in Germany and Italy, he laid hands on the Pope himself, denied his secular rule and granted himself the right to repudiate the gift of Charlemagne. Sent from Rome, Pius VII was brought as a prisoner to Savona and to Fontainebleau. He was not only required to renounce the Papal States and to acknowledge the organic articles, but he was also required to renounce the right of the canonical appointment of the bishops, that is, the sacred bond that that alone could not be torn, namely, the bond whereby the bishops are united with the pope and through him with Jesus Christ.
Given that universal (Catholic) monarchy was a maxim of the First Reich, later an aspiration by the Spanish Habsburgs and the French Bourbons, the association here of universal monarchy with Bonapartist and Jacobinical secularism is interesting—an attempt, perhaps, to deflect liberal accusations of ultramontanes being an imperial fifth column and throw the accusation instead at their use of balance-of-power realpolitik.
As of 1866, things were looking better:
Nowadays the bishops can already leave their dioceses without state permission, gather, be free with Rome, go to Rome themselves, and quench themselves at the source of all authority and truth. The orders and monastic societies have once again taken their place freely and openly, as indispensable aids to the world's clergy in preaching, instruction, education and all the works of mercy... Even Protestants and rationalists have recognized the sanctity and inviolability of this great institution of the papacy, which is the keystone of the whole social order, and the bishops of the whole world, united in a solemn assembly around Pius IX, have pronounced the necessity of the temporal sovereignty of the Pope, as well as the freedom of his spiritual power.
This was a somewhat baffling statement to make, given that the Papal States had been robbed of Romagne, Umbria and the Marches (about 3/4 of its territory) only half a decade earlier, and the Great Powers', particularly England's indifference or even hostility towards the Pope retaining even Rome was not a secret. Five years after writing this, the Kulturkampf and a new wave of anticlerical hysteria would explode, making this a tragicomical prediction. But again one gets the feeling of him trying to flatter a more liberally minded (for the 1860s) reader.
Nevertheless, Keller was ultimately aware this could not last: "In order to justify this passive role, the state makes itself a system of theoretical freedom, which is very similar to the political non-interventionist principle. All this is a truce, not a solution, and the religious question will remain unresolved until the day when the revolution has spoken its last word in political and social terms."
And so the revolution spoke.
"The wars of the revolution and the empire had buried millions of people in vain. They had destroyed what was left of small nationalities and independent polities. After having trampled on all treaties and acquired rights, they had succeeded in making the absolutism of the old regime boundless."
Keller was committed to a Catholic solidarity and was thus sympathetic to the national movements of the Poles and the Balkan Slavs, but not so much the Italians, a divided people. Austria would have to shift its course to better isolate England and Russia, since, according to him, "instead of shaking hands with the Cossack to guard Galicia and Lombardy - a sacrilegious alliance, which they dare call the Holy Alliance - instead of being the outpost of the Eastern autocracy, [the Austrians could instead] be the forerunners of the independence of the Eastern Christians, the avant-garde of civilization, the salvation of Poland and the protection of Europe against Moscovite rule."
Polish nationalism under Dmowski and Pilsudski alike would end up being quite secular. Pilsudski's geopolitical strategy of Prometheism involved stoking national revolts within the Russian Empire, many of them non-Christian Asiatic peoples, thus helping destroy one of the last Christian empires, with Austria-Hungary already being weak and decaying. Again, a strange call by Keller. At the time it was no doubt an attempt to show that ultramontanists can be patriotic citizens, too!—but in retrospect, quite wrong-headed.
So in the end it appears that liberal antipathy toward Christian integralists is quite justified, in terms of the former's self-preservation.