Nobody actually wants to invoke Article 5. The European countries talk a lot, but they don't actually want to do anything serious.

Macron famously said that he would "have to send troops to Odesa" and yet 3 years later there are still no French troops in Ukraine and Russia has captured even more territory and is now actively bombarding Kyiv.

The reality is that, despite their public statements and posture, every leader in the EU secretly hopes USA can broker a peace deal and this all just kinda goes away.