Don't understand.

It is obviously right and proper that Shaker Aamer, who has finally been released from Guantanamo Bay after being imprisoned there without charge or trial for nearly 14 years, should receive compensation for what he's been through.  But why should it be the British taxpayer who foots the bill?  As I understand it, he was captured, arrested or whatever by the Americans, Guantanamo Bay is an American prison and it is solely down to the Americans that he has not been released until now.  So why are we paying?