Unless it be otherwise determined, by reason of some exceptional condition of things, it is expedient to take part in the administration of public affairs. And the Church approves of every one devoting his services to the common good, and doing all that he can for the defense, preservation, and prosperity of his country.

– Libertas 45

[T]hat liberty is truly genuine, and to be sought after, which in regard to the individual does not allow men to be the slaves of error and of passion, the worst of all masters; which, too, in public administration guides the citizens in wisdom and provides for them increased means of well-being; and which, further, protects the State from foreign interference. This honourable liberty, alone worthy of human beings, the Church approves most highly and has never slackened her endeavour to preserve, strong and unchanged, among nations. And, in truth, whatever in the State is of chief avail for the common welfare; whatever has been usefully established to curb the license of rulers who are opposed to the true interests of the people, or to keep in check the leading authorities from unwarrantably interfering in municipal or family affairs; whatever tends to uphold the honour, manhood, and equal rights of individual citizens-of all these things, as the monuments of past ages bear witness, the Catholic Church has always been the originator, the promoter, or the guardian. Ever, therefore, consistent with herself, while on the one hand she rejects that exorbitant liberty which in individuals and in nations ends in license or in thraldom, on the other hand, she willingly and most gladly welcomes whatever improvements the age brings forth, if these really secure the prosperity of life here below, which is, as it were, a stage in the journey to the life that will know no ending.

– Immortale Dei 37-38