●Eisenhower made an open break with Israel in 1956 during the Suez crisis. He knew this was politically risky, but Thomas notes his frustration with Israeli military threats, quoting speechwriter Emmett Hughes: “The whole Middle Eastern scene obviously leaves him dismayed, baffled and fearful of great stupidity about to assert itself.”

I’d guess Obama has similar worries about Israeli Prime Minister Benjamin Netanyahu’s threat to take unilateral military action against Iran and his reluctance to make peace with the Palestinians. Are these two headed for a 1956-style break? That would be bad for both sides, but the atmosphere is poisonous. A bitter nomination battle over Hagel won’t help.

●Eisenhower didn’t want to fight more land wars, and neither does Obama. But each faces continuing global threats — in Ike’s case from an expansionist Soviet Union, in Obama’s case from a still potent al-Qaeda — that require some way to project power. “Eisenhower preferred small-scale covert action over grand military maneuvers,” notes Thomas.