In the last days of the Bush Administration, Washington was abuzz with speculation over who might or might not receive pardons in a final act of presidential clemency.

Most hotly debated was whether George W. Bush would seek pre-emptive pardons for those involved in his controversial “torture” programme to prevent them from being prosecuted.

He did not. Lawyers were at odds over whether he even could without naming names or crimes of which they could be guilty.

Just as probable, it seems, was the Bush Administration’s desire to cut and run without further controversy or legal entanglement, leaving the mess to the incoming president to sort out while betting on a likely lack of appetite for a witch-hunt.

If Mr Obama has gone for the agents who carried out the coercive interrogation condemned widely as torture, he would have to have carried the process all the way up to the top, rooting out every government official, lawyer and operative involved in creating and implementing this policy.

It is still unclear whether he intends to bring action against the lawyers and high government officials who signed off on the program but his opposition to “laying blame for the past” suggests not.

There were no easy decisions here. Mr Obama came to office vowing to heal the divisions of the past. Prosecuting those involved in the torture controversy could look dangerously like a partisan witch-hunt. How high would it go? To Dick Cheney? Almost certainly. To Mr Bush? Quite possibly.

Then there is the question of who knew what. Both Democrats and Republicans sitting on the House and Senate intelligence committees may have been briefed in more detail than they would retrospectively wish. Many senior Democrats are as deep in this one as their Republican counterparts.

Lower down the scale, he knows that prosecution would run the risk of criminalising a vast swath of experienced intelligence agents whom the United States still relies on for its security.

This is hardly the moment in history to send half your intelligence operatives to jail. The vast majority of Americans are sympathetic to the difficult decisions made in the wake of September 11 and while they might not agree with torture out loud, will be happy to write this episode off as the product of an extraordinary moment in history.

These are political issues. The judicial ones are infinitely more complex. America prides itself as a nation under the rule of law, and the law says torture is wrong – even under the extreme pressures intelligence officials faced after September 11.

Critics will say that Mr Obama’s announcement is tantamount to the pardon Mr Bush never granted. That it grants impunity, not just immunity to torturers. Releasing the memos, and vowing that torture will never be permitted again, is a clear attempt to navigate these criticisms, a kind of truth and reconciliation without names.

But it is also not a little hubristic. Mr Obama is not president for life and has the power only to ensure that what happened before does not happen again on his watch. What happens afterwards?

Torture is illegal, however thoroughly and disingenuously Mr Bush’s lawyers contorted the law to try and prove otherwise. Mr Bush never accepted that what happened was torture. Mr Obama has and has decided to let it go – in the national interest, he argues. Americans will probably agree and be grateful that this dark chapter is over. History may not be as kind.

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