Pope Benedict XV had this to say just before World War I.
“Let the Princes and Rulers of peoples remember this truth, and let them consider whether it is a prudent and safe idea for governments or for states to separate themselves from the holy religion of Jesus Christ, from which their authority receives such strength and support. Let them consider again and again, whether it is a measure of political wisdom to see to divorce the teaching of the Gospel and the Church from the ruling of a country and from the public education of the young. Sad experience proves that human authority fails where religion is set aside.”
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