As for what NATO will do,well,I suspect we'll find out during Trump's second term that NATO is now a tiered subscription service and that, conveniently enough,Eastern European nations don't get the full premium package,but something like the Ukrainian subscription plan.
I've been expecting this for a while now. No way they are going to treat countries like Estonia on the same level as Germany, France and the UK.
A 50/50 split to leave the EU is totally terrible, but a 50/50 split to join the EU is completely fine.