Things have come to a strange state of affairs when Washington regards Avigdor Lieberman, Israel's far-right foreign minister, as the voice of moderation in the Israeli cabinet.
While Lieberman has called the soon-to-be-unveiled US peace plan the best deal Israel is ever likely to get, and has repeatedly flattered its chief author, US Secretary of State John Kerry, other ministers have preferred to pull off the diplomatic gloves.
The most egregious instance came last week when Moshe Yaalon, the Israeli defence minister, launched an unprecedented and personal attack on the man entrusted by President Barack Obama to oversee the negotiations between Israel and the Palestinians.
In a private briefing, disclosed last week by the Yedioth Aharonoth newspaper, Yaalon called Kerry "obsessive and messianic," denounced his peace plan as "not worth the paper it was written on," and wished he would win "the Nobel prize and leave us alone."
Yaalon could hardly claim he was caught in an unguarded moment. According to reports, he has been making equally disparaging comments for weeks. Back in November, for example, an unnamed "senior Israeli minister" dismissed Kerry's ideas as "simply not connected to reality ... He is not an honest broker."
On this occasion, however, Washington's response ratcheted up several notches. US officials furiously denounced the comments as "offensive" and demanded that Israeli prime minister Benjamin Netanyahu publicly slap down his minister.
Also showing no signs of remorse, Netanyahu evasively suggested that disagreements with the US were always "substantive and not personal."
With the diplomatic crisis still simmering, Yaalon returned to the theme late last week, telling an audience in Jerusalem that the US and Europe had a "misguided understanding" of the Middle East and denouncing a "Western preoccupation with the Palestinian issue."
Not suprisingly, the Palestinian leadership is celebrating the latest evidence of Israel's increasingly self-destructive behavior. Such outbursts against Kerry will make it much harder for Washington to claim the Palestinians are to blame if, or more likely when, the talks collapse.
The Israeli government is not only hurling insults; it is working visibly to thwart a peace process on which the Obama administration had staked its credibility.
Netanyahu has kept moving the talks' goal posts. He declared for the first time this month that two small and highly provocative settlements in the West Bank, Beit El and a garrisoned community embedded in Hebron, a large Palestinian city, could not be given up because of their religious importance to the "Jewish people."
That is on top of recent announcements of a glut of settlement building, ministerial backing for the annexation of the vast expanse of the Jordan Valley and a new demand that Palestinians stop "incitement."
Even Obama appears finally to be losing hope, telling the New Yorker this week that the chances of a breakthrough are "less than fifty-fifty."
While Netanyahu may act as though he is doing the White House a favor by negotiating, he should be in no doubt of his dependence on US goodwill. He received a timely reminder last week when Congress voted through a $3.1 billion aid package for Israel in 2014 -- plus hundreds of millions of dollars more for missile development -- despite the severe troubles facing the US economy.
In part, Netanyahu's arrogance appears to reflect his personality -- and a culture of impractical isolationism he has long nurtured on the Israeli right.
With Washington pushing firmly for engagement with the Palestinians, this has started to rebound on him. Israeli analysts have noted his growing insecurity, fearful that any concessions he makes will weaken him in the eyes of the right and encourage challengers to the throne. That explains some of his indulgence of Yaalon.