ANALYSIS: It hasn't been a glorious week for American diplomacy, writes Patrick Smyth, Washington Correspondent
On two quite separate fronts events beyond the control of the US have thrown sand in the face of the world's one and only superpower.
In Venezuela the extraordinary reversal of a coup left the US deeply exposed to criticism from regional friends that it was, at best, halfhearted in its defence of democracy, seriously undermining its credibility.
And as he returns, seemingly empty-handed, from the Middle East, the US Secretary of State, Mr Colin Powell, seems also to reflect US failure.
But the two cases are far from comparable.
In Venezuela the US, faced with two alternatives, shot itself in the foot and then retreated, unconvincingly trying to cover up the U-turn.
In the Middle East, Mr Powell's incomplete exercise in Kissinger-style shuttle diplomacy may not yet have been crowned with success but is far from over.
However, a rush to judgment would be premature, and failure can hardly in any case be blamed on him.
Far from retreating, President Bush yesterday made clear the US would continue to engage.
That, in itself, is an important commitment from a man whose instincts tell him that such engagement in the murky and morally ambiguous conflict simply confuses his greater message that the war on terrorism is clear-cut with no room for neutrality.
Mr Bush's uneasiness with this world was reflected in his ultimatum to both Israelis and Palestinians last week that was ignored by both sides, an embarrassing lesson on the real limits of his power of influence.
Since then his spokesman has tried to play down its mandatory character, insisting it was only a request.
And he knows he may have to pay a price domestically - his Assistant Secretary of Defence, the hawkish Mr Paul Wolfowitz, was vigorously booed at the 100-000-strong Washington pro-Israeli rally on Monday when he suggested innocent Palestinians may have lost their lives. On the floor of Congress a powerful pro-Israeli front of otherwise liberal Democrats and conservative Republicans is chafing at every criticism of Israel or attempt to restrain it.
The truth is that, at this stage, it is the fact of rather than the product of Mr Powell's mission which is a step forward.
As he left the US 10 days ago Mr Powell, and saner observers, warned that he was unlikely to come back with a ceasefire and he has not.
But if the possibility of peace talks are currently ruled out by the continuing Israeli occupation of Palestinian cities, Mr Powell's visit has at least opened a window of opportunity when that occupation ends by brokering wide acceptance for an international conference, probably in June.
And fears that the knock-on effect of the violence might trigger a regional conflict as attacks on Israel's northern border escalated have also been eased by Mr Powell's visits to Beirut and Damascus.
But the central US strategic objective as he set off, of forcing the moderate Arab states to confront Mr Arafat and possibly even assisting in his replacement with a more acceptable interlocutor, was never realistic.
As Israeli action escalated such an outcome became even less likely. And Mr Arafat saw his own standing soaring.
Mr Powell will be back, however.
And he left Assistant Secretary of State, Mr Willam Burns, in place to continue the work.
General Anthony Zinni is returning to the region and is likely also to be followed by the head of the CIA, Mr George Tenet, to promote security co-operation between Israel and the Palestinians. Although Mr Powell has faced some domestic criticism for his willingness to meet Mr Arafat, that has largely come from those hostile to US involvement.
His reputation remains largely intact, and while Mr Bush remains committed to engagement few here can imagine anyone better able to carry out the task.