The warnings issued by Putin to not interfere and the West's "drawing a line in the sand" reminds me a bit of the Cuban missile crisis (though it's Russia who's

The warnings issued by Putin to not interfere and the West's "drawing a line in the sand" reminds me a bit of the Cuban missile crisis (though it's Russia who's claiming a free Ukraine weakens their sovereignty. But going back further in time, we've seen that doing nothing (when Hitler invaded Poland) is not diplomacy but rather emboldened him that the world would stand-by and do nothing.