
Both Communism and Socialism are ideologies specifically condemned by the Catholic Church for hundreds of years. Both are completely unacceptable philosophies for any devout Catholic to hold. Pope Saint John Paul Il focused many of his encyclicals on the evils of Communism, many of which he witnessed firsthand in Poland. Catholics making a "political alliance" is at best spiritually dangerous and at worst full heresy. Be extremely careful with the ideologies you associate with Catholic teaching.
what is your perspective on why they were supposedly condemned but not capitalism or any other way of doing things? I see capitalism as inherently exploitative. Socialism has been done in bad ways (mostly bc of fascism from what i can tell) but people also attack socialism to justify the erosion of social services so idk. I think we all want to find the least harmful way to do things