Putin drew his red line, but he should delude himself that Washington is listening or that it will take him seriously. He may well have to prove his red line is a real red line. From Paul Craig Roberts at paulcraigroberts.org:
Update Dec 14: As I wrote, Washington intends to keep the “Russian invasion of Ukraine” narrative alive: https://www.rt.com/russia/543124-us-considering-send-troops/
It is both a good thing and a bad thing that Putin got the point across to Washington that Russia will not permit NATO moving into Ukraine. It is good because a Russian foot finally came down. It is a bad thing if it convinces the Kremlin that, finally, Washington is listening.
Washington is not listening, and the Kremlin might again be lost in self-deception.
For Washington, it is more useful for Ukraine to be continually threatened by Russia than to be protected by NATO. If Ukraine is protected, the orchestrated “Russian threat” fades away. What other country can Russia be alleged to be preparing to attack?
Washington is happy to keep Ukraine out of NATO as this keeps the real problem festering. The West claims that the Russians who inhabit Eastern Ukraine in the breakaway republics are rebels whom the Ukrainian army is justified in putting down. The Kremlin apparently agrees as the Kremlin has refused to recognize the endangered republics. Thus, the war there will continue.
It is this war that is dangerous, and it is the Kremlin that tolerates this dangerous war. Eastern Ukraine for centuries was part of Russia. Lenin and Stalin moved the Donbas Russians into Ukraine and Khrushchev incorporated Crimea into Ukraine. Whether this was done for administrative convenience or to add Russian nationals to the Ukraine, or in the case of Khrushchev, himself Ukrainian, to make amends for the Ukrainians he had murdered, I don’t know. It did not matter much at the time as Ukraine was just a province of the Soviet Union. You were Soviet whether you were in Russia or the Ukraine.
The war is dangerous, because the Kremlin has let seven years of the war go by without stopping it. Russians who feel national ties are getting frustrated that Russians in the breakaway republics are being killed by Ukrainian neo-nazi forces supplied by Washington. Russia has provided arms to the breakaway republics, but it has permitted the neo-nazi Ukraine at Washington’s direction to continue its attacks, which continue to take Russian lives.