As snubs go, this one takes some beating. Israel's announcement that it plans to build 1,600 new homes in East Jerusalem comes at the very moment that US Vice-President Joe Biden is on its soil, talking up prospects for peace.
"I think we are at a moment of real opportunity," Mr Biden said apropos of what is still quaintly referred to as the "Middle East peace process". If so then that window of opportunity has been slammed shut by the new settlements announcement.
The result was the remarkable diplomatic spectacle of the White House "condemning" the behaviour of a country to whose security the Vice-President, hours earlier, had pledged America's "absolute, total, unvarnished commitment".
It is all very well for Israel to point out that the announcement was "procedural", that actual work on the new homes will not start for two years, and that Benjamin Netanyahu, the Israeli Prime Minister, was as unaware of it in advance as was Mr Biden himself. It is hard to imagine that such a news release would have been similarly timed if George W. Bush were still in the Oval Office.
The Biden visit had been intended to repair relations between Israel and its key ally and most important patron, after the strains caused by President Obama's demand for a freeze on settlements, and Israeli complaints that he was too sympathetic to the Arab cause. The US demand was subsequently watered down, to the point that Hillary Clinton hailed an Israeli offer to "restrain" settlements as an "unprecedented concession".
Those words were infuriating enough for moderate Arab governments. Israel's latest gesture must have scotched remaining hope of early progress in the "peace process". It is also a sign of Israel's belief that no US President will dare stand up to it.