Summary
Germany warns that Russia is rearming faster than expected, replacing war losses and stockpiling tanks, missiles, and drones.
Putin has redirected Russia’s economy to fuel its military, aided by supplies from Iran and North Korea.
While there’s no clear evidence of plans to attack NATO, Russia is creating the conditions for it.
On the Ukraine front, Russian forces are advancing in south Donetsk, nearing strategic town Pokrovsk, a key supply hub and coal mining center.
Analysts suggest Putin aims to seize land before potential peace talks.
https://www.nato.int/cps/en/natohq/topics_110496.htm
As far as mutual defence treaties go Article 5 is worded very strongly and any nation failing to provide assistance to a member nation would find itself a pariah.
The chances that an article 5 event involving Russia doesn’t trigger full scale war are slim to none.