From Tom Wright at the Guardian:
Couldn't be any more on the nose!
America's exceptionalist justice
Consider the following scenario. A group of Irish republican terrorists carries out a bombing raid in London. People are killed and wounded. The group escapes, first to Ireland, then to the US, where they disappear into the sympathetic hinterland of a country where IRA leaders have in the past been welcomed at the White House. Britain cannot extradite them, because of the gross imbalance of the relevant treaty. So far, this seems plausible enough.
But now imagine that the British government, seeing the murderers escape justice, sends an aircraft carrier (always supposing we've still got any) to the Nova Scotia coast. From there, unannounced, two helicopters fly in under the radar to the Boston suburb where the terrorists are holed up. They carry out a daring raid, killing the (unarmed) leaders and making their escape. Westminster celebrates; Washington is furious.
What's the difference between this and the recent events in Pakistan? Answer: American exceptionalism. America is subject to different rules to the rest of the world. By what right? Who says?