Had enough of a brain to know that Kiev was an integral part of the Russian state, and would not, in their wildest dreams, have risked war over the question.
Ukraine for the last 1000 years or so has been a round-robin between being part of Russia, part of some other empire, and its own nation, or even its own empire. Whether a Kissinger-led Nixon, or a Shultz/Rumsfeld-led Reagan, would have chosen to make Kiev an issue, is one question, but my point was that, if they had chosen to make it an issue, their private threat/promise to Khrushchev, or Brezhnev, or Andropov, or Gorbachev would have been believed, but no threat Obama says is believed anymore.