Since that's going to be cut back Germany and to a lesser degree France are the only countries left to take up the slack.
I don't have a really strong opinion either way in terms of what's happening in the US or in Europe, but the argument claiming that there's no real reason to spend money on the military seem pretty disingenuous re. Russia.
What's the real chances that Russia would do something like a land invasion of Europe? Really, really small.... But military spending is the thing helping keep those chances very small.