The best time may have been 10 years ago — I don’t know enough to argue that either way — but the war is now going to cost Russia 10% of its GDP, and appears to already be interfering with Russia’s ability to maintain the effectiveness (such as it is) of its armed forces.

But this isn’t the only thing going on, lots of governments are giving actual weapons to Ukraine as well. If he was rational, sadly that appears to be a big if, that would probably help deter Putin too.

Weaken the image and actual strength of the Russian Army and it puts into question their position in the various -stan's on their southern border. The Red Army was a terrifying concept during the Cold War.

I upvoted you for the "...it’s pure economic suicide and does nothing to stop the war anyways..." part of your comment. But does your remark about dictatorships include all dictatorships, or only the ones who aren't on our side?

In my opinion, “all dictatorships” but US/EU prefer realpolitik and try to collaborate with some (Saudi/UAE for oil, China/Vietnam for cheap labour, …). Might eventually backfire (in process re:China)