You never cut off diplomatic channels, even in war, if you can help it. It’s important to note that the United States has kicked 12 Russian diplomats out of the UN, not as an arbitrary punitive measure, but because they were caught doing disqualifying things (in other words, spying).
Putin has a history of putting spies in diplomatic positions in order to give them cover, and the U.S. has a history of monitoring Russian diplomats as if they were spies. This is nothing new in that sense.
The U.S. possibly already knew Russia’s UN diplomats were spies, and instead of expelling them, merely monitored them to see what could be learned. If so, why expel them now? It weakens Russia’s ability to influence the current UN general assembly.
If that seems unfair, then Putin shouldn’t have sent spies to the UN in diplomatic positions to begin with. He can replace them with actual diplomats if he wants – which he won’t.
Bill Palmer is the publisher of the political news outlet Palmer Report