Historically NATO has said no to Ukraine. That they would not go into Ukraine. First you say they should have gone
into Ukraine when Putin first massed his troops. Now you say a long standing position of NATO's is Putin's red line.
"Putin Red Line...NATO, Don't go into Ukraine, or else"
Don't think you intended to drift there, but you are using one of Putin's top talking points now.
It was Plato who said, “He, O men, is the wisest, who like Socrates, knows that his wisdom is in truth worth nothing”