Europe isn't suddenly grow a pair of balls. We're pathetic right now.
Yeah. Your politicians aren't able to make the hard choices of war. Or of adequately funding a military.
Fighting two utterly devastating continent wide wars has made all of the traditional powers disinclined to build a large army.
Times change. Germany and France weren't, historically, reluctant to fund large armies with the latest hi-tech weapons systems - even back in the days when gunpowder was hi-tech.
A few decades of butter rather than guns doesn't imply an inability to return to a heavily armed state, but it's really not been needful with the EU essentially eliminating conflict within western Europe, and Uncle Sam providing a nuclear umbrella to deter any external threats.
The problem with Russia is salami tactics. Nuclear deterrence requires a clear and unequivocal "red line" that triggers an overwheming, even if suicidal, response. If a belligerent is careful to only ever make incremental changes, allowing them to become the new normal before taking another step forward, it makes nuclear forces irrelevant.
NATO's strength lies, not in its arms themselves, but in its absolute borders - an enemy who transgresses those borders renders themselves liable to the full retaliatory might of the entire alliance, up to and including the use of nukes.
As Kennedy said, "It shall be the policy of this nation to regard any nuclear missile launched from Cuba against any nation in the Western Hemisphere as an attack by the Soviet Union on the United States, requiring a full retaliatory response upon the Soviet Union". To deter, you have to clearly declare a set of actions that will meet an insane level of violence in response - and you have to be believed.
As long as any incursion by foreign troops onto NATO territory was regarded by America as an attack by the Soviet Union on the United States, Germany didn't need a big army. The demise of the Soviet Union has brought doubt, and the appearance of non-NATO, but not pro-Russian, nations in the gap between West Germany and Russia, still more doubt.
The obvious way to reduce the latter was to invite those new nations to join NATO. But that doesn't fit well at all with Russian expansionism. Hence Vlad's abortive attempt to take Kyiv, and hence all of Ukraine, in a short victorious war that would be over and done with while Western Europe was still trying to decide whether to respond.