Quote Originally Posted by Tribesman
It would certainly appear that the only reason for his change in policy is the US involvement.
So far this seems likely to be the best explanation.

Sad, really. It's not a wise basis for policy in realpolitik terms, and given our propensity for tossing out administrations after no more than 12 years, it doesn't even speak to securing a means of influencing U.S. policy over the long haul -- vindictiveness against one U.S. admin does not mean winning points with the successors, and even if it did, the successorts are only there for so long anyway.