We are behind in some weapons systems and are extremely vulnerable defensively. NATO countries need to harden their infrastructure while providing training and resources to those willing to fight for Ukraine and perhaps those related to other recently acquired Russian lands. The marriage of eager fighters, insurgency specific technology, technique, and resources for insurgency warfare will be the foundation of bringing down Russia if they continue on their present path, whether nuclear or not.
Economic sanctions against Russia over time along with harassing attacks on their infrastructure by partisans will cause Russia to fail economically, fall behind technologically, and to divert otherwise productive people to defense. Further, quality of life for Russian people will decline, causing increasing civil unrest including protests. Was is Putin going to do? Put everybody in jail?
The US has a massive number of people who own firearms, many of whom are ex-military and retired police who can be activated to protect against sabotage. We can accelerate anti-missile defense system development and look to efficiently militarize private vehicles such as SUVs, civil aircraft, and civil boats. Creating cross platform, cross class, and extra-class parts compatibility will allow us to multiply our defensive and even offensive capabilities at relatively little extra cost. A side benefit to doing this would be increased innovation and more efficient cross training. Further, we would be better prepared for natural disasters and even supply chain bottlenecks.
I have much more specific information to share on this, but work beckons soon.