As one of the pioneers of the analogy I feel the irony in how it has quickly gone from scandal to cliché to compare Putin to Hitler, for better and for worse. Certainly Putin’s arrogance and language remind us more and more of Hitler’s, as does how well he has been rewarded for them. For this he can thank the overabundance of Chamberlains in the halls of power today — and there is no Churchill in sight.

As long as it is easy, as long as Putin moves from victory to victory without resistance, he gains more support. He took Crimea with barely a shot fired. He flooded Eastern Ukraine with agents and weaponry while Europe dithered. The oligarchs who might have pressured Putin at the start of his Ukrainian adventure are now war criminals with no way back. The pressure points now are harder to reach.

The Russian military commanders, the ones in the field, are not fools. They are aware that NATO is watching and could blow them to bits in a moment. They rely on Putin’s aura of invincibility, which grows every day the West refuses to provide Ukraine with military support. Those commanders must be made to understand that they are facing an overwhelming force, that their lives are in grave danger, that they can and will be captured and prosecuted. To make this a credible threat requires immediate military aid, if not yet the “boots on the ground” everyone but Putin is so keen to avoid. If NATO nations refuse to send lethal aid to Ukraine now it will be yet another green light to Putin.