Matthew Yglesias is basically right about the substantive implications of the New START fight:
This very fact of hyper-partisan stalling around START, however, is exactly what's so disturbing about the current situation. Arms-control proponents hoped START would be just one small step toward a more ambitious agenda that was supposed to include ratification of the Comprehensive Test Ban Treaty and other steps to revive the international consensus around nuclear disarmament. Unlike START, some of these would be genuinely controversial within the national-security community and provoke meaningful opposition from elements of the military and the defense contracting world. And after the START experience, the odds of getting any further look bleak. The Obama administration has had to pull out all the stops to have a chance of securing ratification of a treaty that mostly just prevents us from moving backward. Fundamentally, whether START passes or fails the real message this week has been that the dream of major new steps toward disarmament is dead.
Right. So the GOP turned new START into a partisan battle, which turned the ratification of a non-controversial treaty into a huge political victory for the White House. But what that means future steps towards disarmament are unlikely, not only because the first minor step was so controversial, but because this administration doesn't like to take on fights it expects to lose.
So in the short term, Republicans end up with an unnecessary political loss. But even if they didn't mean to, they've managed to make future efforts towards disarmament less likely to succeed.