So what is Obama going to do when Russians/Seperatists shoot down a US airliner or an airliner containing several Americans? I'm betting such thoughts makes Putin giggle like a little girl.
Elections do indeed have consequences.
What will any US politicians do? I'm obviously no fan of Obama, but what will any Republicans do, other than bluster and perhaps pass sanctions that have no real meaning to Russia? It will be hard to prove (and may not be the case) that Russia had any direct involvement. It would be difficult to make a case for direct military response to Russia over something a separatist group likely did, or will get the blame for.
The US as it stands today, does not have the testicles to poke the sleeping Russian bear, let alone the Russian bear of today, which is kind of awake and grumpy. Even if we did, we are two nuclear powers. That's a dangerous game.