The CIA was actively involved in the Maidan revolution, which sought to pull Ukraine out of Russia's sphere of influence and into the EU / NATO. Obviously this is antagonistic towards Russia, especially when they have so few natural barriers to defend against invasion of their land. Look at how quickly the Wagner group reached Moscow after defecting from the Ukrainian front.

If the shoe were on the other foot, and China had supported a revolution in Mexico and was setting up military bases, the American government would not take it lightly. The US would cook up some reason to wage war against Mexico as a continuation of the Monroe Doctrine. These wars are not about good and evil, as much as it's about empires and power.