This is possible for only one of the following 2 reasons:
a) the modernists have stopped opposing Catholicism and have converted, or
b) the Catholics have stopped opposing modernism and have surrendered.
"No man can serve two masters. For either he will hate the one, and love the other: or he will sustain the one, and despise the other. You cannot serve God and mammon." (Matthew 6:24)
"Bear not the yoke with unbelievers. For what participation hath justice with injustice? Or what fellowship hath light with darkness? And what concord hath Christ with Belial? Or what part hath the faithful with the unbeliever? And what agreement hath the temple of God with idols? For you are the temple of the living God; as God saith: I will dwell in them, and walk among them; and I will be their God, and they shall be my people. Wherefore, Go out from among them, and be ye separate, saith the Lord, and touch not the unclean thing: And I will receive you; and I will be a Father to you; and you shall be my sons and daughters, saith the Lord Almighty." (2 Corinthians 6:14-18)
"A man that is a heretic, after the first and second admonition, avoid: Knowing that he, that is such an one, is subverted, and sinneth, being condemned by his own judgment." (Titus 3:10-11)