By Jonathan Marcus
Diplomatic correspondent, BBC News
More than half a year after the Israeli air strike that destroyed the alleged nuclear reactor under construction in Syria, Washington's release of what it says are still images of the facility before the raid amounts to the diplomatic equivalent of throwing a very large rock into a deep pool.
The alleged reactor was destroyed by Israel in 2007
The ramifications could be considerable, both for the Middle East and for the future of North Korea's own nuclear weapons programme.
Further distrust has been sown between the United States and the UN's nuclear watchdog - the International Atomic Energy Agency (IAEA).
And even on Capitol Hill Democrat lawmakers are angry that the administration apparently sat on this evidence for some considerable time.
Shades of Iraq?
Briefings about alleged weapons of mass destruction programmes have a lot to live down in the wake of the US experience in Iraq.
Everyone remembers the time in February 2003 when then US Secretary of State Colin Powell went to the United Nations armed with tape-recordings and images to make the case about Iraq's weapons activities.
The briefing - seemingly the best that the combined US intelligence agencies could come up with - turned out to be misleading to say the least. Subsequently, no weapons were found.
Perhaps mindful of the mistakes of the past, the ten-minute video released by the Bush administration in an effort to prove the Syria-North Korea connection is less ambitious and more focussed.
It uses still images which, it is claimed, were taken inside the facility during its construction.
There is of course no independent way to verify this.
But an initial analysis suggests that the pictures show a gas-cooled graphite moderated reactor of a very similar type to the North Korean model at Yongbyon.
At face value at least, the US evidence is compelling.
But the revelations raise as many questions as they answer.
What was this reactor for? There are no signs of the ancillary facilities needed if it was for power-generation.
But then, equally, there are no signs of the other elements of a bomb-making programme either - a plant to separate out the plutonium and a factory to actually assemble a weapon.
If, as the Americans say, the reactor was close to completion, where would its uranium fuel have come from?
But beyond the practical and technical questions the most pressing uncertainties are political and diplomatic.
Above all, why did the US go public now? And was this an effort to further isolate Syria or to bring additional pressure on North Korea?
The underscoring of an alleged nuclear link between Pyongyang and Damascus certainly harms both governments.
For all the talk of renewed conflict between Israel and Syria, there has also been a good deal of talk about a possible deal over the Golan Heights as well.
The signals have been complex and contradictory. But highlighting a clandestine Syrian nuclear programme now might serve to reinforce Syria's isolation.
Without US brokerage, any talk of a Syria-Israel deal is illusory.
Some analysts believe that the decision to go public on the evidence of the Syrian reactor project may be the culmination of the playing out of competing currents within the Bush Administration.
In this scenario it is a victory of the more hawkish voices, who fear that President Bush might be going soft as his term of office draws to a close.
The US says there were similarities between the Syrian and North Korean reactors
In their view, the Americans should not accept any dealings with Syria, nor should it make the concessions required to North Korea to keep alive the deal to roll back its nuclear programme.
Such arguments appear strongest with regard to North Korea.
It is clear that conservative voices both inside and outside the Bush administration see the proposed agreement with North Korea as fatally flawed.
More liberal arms control experts also hold that view. "It stinks," one told me, "but perhaps the US should hold its nose in the hope of keeping the negotiating track open".
So were the intelligence revelations intended to anger Pyongyang to damage any chance of a deal?
Or was this a clearing of the air ahead of further progress?
Interestingly, the chief US negotiator, Christopher Hill, has now noted that in the US view, nuclear co-operation between North Korea and Syria is no longer continuing.
During the coming weeks it will be interesting to see how things unfold. Will Syria-Israel tensions be stoked up? Will Pyongyang walk away from the negotiating table or offer up the long-delayed description of its nuclear activities?
The way in which the US apparently sat on the evidence for so long has also angered many people.
Mr Bush's critics on some of the powerful congressional committees were dismayed that they had not been taken into the administration's confidence earlier.
Also clearly angry is the head of the IAEA, Dr Mohamed ElBaradei.
He says the US gave his organisation its evidence about the Syrian reactor only on the same day that it briefed legislators on Capitol Hill.
A statement from the IAEA says that Dr ElBaradei "deplores the fact that this information was not provided to the agency in a timely manner". It is now going to investigate further.
But with the site of the alleged reactor razed, a new building constructed over it - and the Syrians unlikely to provide access - it is hard to see how far the IAEA's investigations can go.