By David Bamford BBC correspondent in Washington

If the US administration was embarrassed by Israel's air strike on Syria, it didn't show it.

Bush refused to criticise the Israeli air strike

President George W Bush was quick to repeat his standard line that follows atrocities against Israeli civilians, complete with his customary contradictory caveat.

Mr Bush said Israel had the right to defend itself and should not be constrained from doing so; at the same time, Israel should avoid escalating tension in the region.

Meanwhile, Mr Bush's spokespeople have been filling out other aspects of the administration's formal Middle East position.

The US is not inclined to allow any UN Security Council resolution condemning Israel's action that does not take into account the killing of 19 Israeli civilians that preceded it.

And the onus for preventing all violence lies with the Palestinians, not the Israelis, and their willingness to crack down on terrorism.

Shot across Syria's bows

There is a reasonable likelihood that Israel's chosen target in Syria was not an operational Islamic Jihad base but probably empty facility once used as a training camp by the all but defunct Palestinian group known as the PFLP-General Command.

Washington wants Syria to break its ties with Palestinian militant groups

It is also reasonable to assume that all parties in the dispute know this.

While it is in the interest of Israeli Prime Minister Ariel Sharon to highlight the raid as a blow to Islamic Jihad in response to the Haifa attack, it is also in Syria's interest to loudly protest this "murderous" violation by Israel of international law.

In reality, both the protagonists and the US understand the attack for what it was - a limited shot across Syria's bows.

Nevertheless, this was Israel's first incursion of any size into Syria for 30 years.

The US is very concerned that the Israelis do not overstep the mark and destabilize the region as Washington endeavours to resuscitate its flagging Middle East peace road map.

Nor should Syrian President Bashar al-Assad be so exacerbated by Israeli actions so as to further undermine US interests in Iraq.

Implied threat

Washington has had limited success in persuading Syria to break ties with Palestinian militant groups and with Hezbollah in Lebanon.

Syria said the Israeli attack was "military aggression"

Their offices have been closed in Damascus, but they remain active on Syrian soil, the State Department said on Monday.

It believes Syria has allowed militants to pass through its border to Iraq to fight US troops there. The US Government, egged on by hawkish strategists, says Syria may be attempting to develop offensive chemical or biological weapons.

Syria is one step away from being added to the list of countries that form President Bush's axis of evil, the Washington hawks warn.