Nothing is more deeply etched into US foreign policy than standing by Israel, and suggestions made by some conservatives last week that Mr Obama was chafing at that compact were hardly to be taken seriously. Nor is America about to join in any call for Israel to be brought before the International Criminal Court for crimes against humanity for its actions in Gaza – if only because, as the main supplier of its arms, that would be a risky tack.
Yet there are times when the friendship can be uncomfortable, and that was on full display through most of last week when civilian casualties in Gaza were soaring and, in particular, when destruction came to a UN school in Gaza with the loss of as many as 20 lives.
When it is not at war, Israel has tested not just Mr Obama, but also George W Bush and Bill Clinton before him, with its settlement building in the West Bank.
A Washington Post-ABC News poll last week confirmed what he could have guessed: 52 per cent of Americans disapprove of his handling of the Gaza emergency, while 39 per cent approve. And a Pew survey, released before the attack on the school, found that only 19 per cent of Americans blamed Israel for the current violence while twice as many, 40 per cent, placed the blame on Hamas.
But there is another interesting divide in the US which, when this crisis has settled, the Israeli leadership might at least want to heed. A new Gallup poll finds that while Americans aged over 65 support Israel’s actions by a margin of 24 points, those under 30 oppose them by a margin of 26.
American tolerance with Israel, in other words, might be weakening.