The Budapest accord says that we do owe Ukraine. Like it or not. 

I don't know how "conservatives" somehow forgot that Russia is always a threat. 

If Russia takes Ukraine, it's a threat to Europe, Poland, Lithuania, etc, etc, etc, etc. At some point it will be our problem. 

Ukraine is atritting Russia for the low, low cost of essentially U.S. hand me down weapons. It's a bargain.