A few bureaucrats with zero military power opening their mouths doesn't give a country the right to invade a neighbor who didn't even make that statement. Not to mention that those statements weren't made until after Russia proved itself to be a military aggressor by invading that neighbor.
And the Monroe doctrine has been dead for a very long time.
That is absolutely load of horse manure.
We promised the Russians no eastward expansion of NATO and expanded to their border.
Ukraine promised to be neutral toward Russia in its Constitution in 1996 and then allowed us, the CIA and NATO to foment an illegal coup and install a government hostile to both Moscow and the ethnic and cultural Russian population in the annexed areas.
We and NATO proceeded to fund, arm and train a 600,000 man Ukrainian army on Russia's border.
If Russia or China had done anything like that in Mexico, WE, JUSTIFIABLY, WOULD HAVE INVADED.