By Daniel Sandford
BBC News, Washington
Abdelbaset Ali al-Megrahi is 57 and has terminal cancer
"Compassion? Compassion for him?"
Susan Cohen's disbelief at the decision to release Abdelbaset Ali al-Megrahi on compassionate grounds is a widely-held emotion in the United States.
Her daughter Theodora Cohen was one of 35 students from Syracuse University in New York State who died in the Lockerbie bombing.
She has followed the trial, the failed appeal and now the release of the man she believes was responsible for killing her daughter and 269 others.
She does not think he had sole responsibility, but she is as certain as she can be that he was the man who planted the bomb.
She cannot comprehend why a mass murderer of such infamy would be freed rather than treated for his cancer in prison.
And she understands even less why he would be allowed to return to the country she holds ultimately responsible for the bombing.
That strength of feeling has left President Barack Obama's administration in a difficult position.
Under the deal that led to Libya handing over Megrahi to the Scottish justice system, the Americans effectively gave up any chance of putting him on trial themselves.
Barack Obama had requested that Megrahi did not get a special welcome
Back in 1999 the expectation was that he would serve a minimum of 27 years of his life sentence.
Now he has been allowed home to die and the Americans had no power to stop it.
All they could do was lobby hard and use strong diplomatic language like "mistake", "inappropriate" and "absolutely wrong".
But they had little leverage over the man who had the ultimate power to make the decision, the Scottish Justice Secretary Kenny MacAskill.
The transformation of Libya's relationship with the US and Britain only makes things more complicated.
Colonel Muammar Gadaffi was told that if he renounced terrorism and his nuclear ambitions then he would be welcomed back into the fold.
Only last month he was photographed shaking hands with President Obama and the British Prime Minister Gordon Brown, and all this in the build-up to the 40th anniversary of his revolution.
He has kept his side of the bargain, so no-one had the stomach for a return to the anti-Libyan rhetoric of the 1990s.
The compromise appears to have been strong words in public, but an acceptance that in the end the decision was up to the Scottish justice secretary.
There is not likely to be any long-term damage to US-British relations, or even US-Scottish relations so far as they exist.
As for the Libyans, President Obama had no condemnation for them either, though he did say that the US had been in touch to make sure that Megrahi did not get any kind of special welcome, and to request that he is kept under house arrest.
Not that the Americans have any control over that. They could only ask nicely and hope the Libyans oblige.
Having got what he wanted, it is up to Col Gaddafi whether he helps the American government out of its difficulty, and makes sure that Megrahi's final days are spent with his family in obscurity.