Nato’s failure to save Ukraine raises an existential question: what on earth is it for? | Simon Tisdall

The military alliance is turning 75. But there's little to celebrate in Kyiv, as Putin's forces continue their bloody advance

Nato's grand 75th birthday celebration in Washington in July will ring hollow in Kyiv. The alliance has miserably failed its biggest post-cold war test - the battle for Ukraine. Sadly, there's no denying it: Vladimir Putin is on a roll.

Advancing Russian forces in Kharkiv profit from the west's culpably slow drip-feed of weaponry to Kyiv and its leaders' chronic fear of escalation. Ukraine receives just enough support to survive, never to prevail. Now even bare survival is in doubt.