Russia isn't the most dangerous threat. They couldn't even roll over Ukraine last year (and until now...). Their leadership is incompetent, they went in under false assumptions (i.e. Ukraine would be easy), and while they are now adapting, they have become mired in a situation where the only question is how badly they will lose. Plus, as an added bonus, they motivated several nations to join NATO (and others to live up to their NATO commitments). Great job, there, Vlad!

China, on the other hand, is a huge threat. They are claiming most of the South China Sea as their territorial waters, despite several international rulings to the contrary. Those waters see a huge amount of merchant traffic, which they appear to want a piece of. They are not shy about challenging US warships making transits in international waters, they are trying to seize islands in the Philippines, and they are becoming ever more bellicose regarding Taiwan. Russia is a mess. China may be the next serious war.