By Paul Adams
Diplomatic correspondent, BBC News
In the Middle East, today's preoccupations can sometimes overcome yesterday's enmities.
Israel is one of the largest recipients of US military aid
And when the preoccupation is a nuclear-armed Iran, this can have surprising results.
Hence we have the spectacle of an Israeli prime minister saying he "understands" Washington's desire to sell state of the art weaponry to Saudi Arabia.
Iran says it is pursuing nuclear technology for purely peaceful purposes, but widespread international scepticism has led opponents to shore up defences.
Israel, which is traditionally wary of arms sales to its Arab neighbours, has welcomed Washington's $13bn (£7.5bn) package of high-tech support for Saudi Arabia and the Gulf states.
When the stated aim of such assistance is, in the words of Secretary of State Condoleezza Rice, "to counter the negative influences of al-Qaeda, Hezbollah, Syria and Iran", then it is not hard to see why Israel's Prime Minister, Ehud Olmert, found nothing to criticise.
The war in Iraq goes on, but the administration realises that it has to restore the faith of its allies in the region
Mr Olmert was also able to point to a whopping 25% increase in the level of US military assistance to his country as proof that Washington remains as committed as ever to preserving Israel's decisive military edge over the Arabs.
Some Israeli right-wingers sounded notes of caution, warning that Israel could not be sure that governments which currently posed no threat would not be toppled by forces with very different views.
But fear of Iran and its regional influence among Shia Muslims has trumped all other concerns.
Last summer, when Israel attacked Lebanon in an attempt to destroy Iranian-supported Hezbollah, the region's Sunni regimes were uncertain how to respond.
They did not like what they saw as an indiscriminate attack on Lebanon, but they harboured a keen desire to see Hezbollah confronted and Iranian influence checked.
Israeli leaders insisted they were doing the region's anxious Sunnis a favour, and Washington sensed that a new alignment of interests offered possibilities.
This summer, perhaps, we are seeing the fruits of America's new thinking.
The war in Iraq goes on, but the administration realises that it has to restore the faith of its allies in the region. Investing in their security is one way of doing this.
But by itself, it is not enough. And so we see from George Bush expressions of renewed commitment to the Middle East peace process and the creation of a viable Palestinian state.
The two aspects of this new strategy will be on view as the president sends Condoleezza Rice and his Defence Secretary, Robert Gates, on a wide sweep through the Middle East in coming days.
Back home in Washington, the policy has its opponents.
Despite Mr Olmert's welcome for the move to sell arms to Arab governments, some congressmen have made it clear they will oppose the move.
Their views will have been bolstered by Washington's former ambassador to Baghdad, Zalmay Khalilzad, who told CNN that Saudi Arabia was undermining efforts to stabilise Iraq.