4 Now if this excessive love of self and of one's own, by an abuse of the legitimate care for our country and an undue exaltation of the feelings of piety towards our own people (which piety is not condemned but hallowed and strengthened by the right order of Christian charity) encroaches on the mutual relations and the ties between peoples, there is hardly anything so abnormal that it will not be regarded as free from fault; so that the same deed which would be condemned by the judgment of all when it is done by private individuals, is held to be honest and worthy of praise when it is done for the love of the country. In this way, a hatred, which must needs be fatal to all, supplants the Divine law of brotherly love which bound all nations and peoples into one family under one Father who is in Heaven; in the administration of public affairs the Divine laws, which are the standard of all civic life and culture, are trampled under foot; the firm foundations of right and faith, on which the commonwealth rests, are overturned; and, lastly, men corrupt and obliterate the principles handed down by their ancestors, according to which the worship of God and the strict observance of His law form the finest flower and the safest pillar of the state. Furthermore - and this may be called the most perilous of all these evils - the enemies of all order, whether they be called Communists or by some other name, exaggerating the very grave straits of the economic crisis, in this great perturbation of morals, with extreme audacity, direct all their efforts to one end, seeking to cast away every bridle from their necks, and breaking the bonds of all law both human and divine, wage an atrocious war against all religion and against God Himself; in this it is their purpose to uproot utterly all knowledge and sense of religion from the minds of men, even from the tenderest age, for they know well that if once the Divine law and knowledge were blotted out from the minds of men there would now be nothing that they could not arrogate to themselves. And thus we now see with our own eyes - what we have not read of as happening anywhere before - impious men, agitated by unspeakable fury, shamelessly liking up a banner against God and against all religion throughout the whole world.
Source: Caritate Christi Compulsi (Vatican.va)