The relationship has often been stormy. But the US likes the way Pakistan is fighting Taliban extremists and Al Qaeda and is willing to speed along military aid. Help with nuclear power is another matter.
Obama wants to triple public financing for new nuclear power plants, even as he nixes funds for storing commercial radioactive waste. The policy may be calculated to win votes for climate change legislation, but critics say it's not 'coherent' and carries new security risks.
Shrinking their nuclear arsenals is not the issue, as US and Russia halt talks on the next START treaty until after the holidays. Verification and inspection regimens look to be the sticking points.
Iran rejected a UN-brokered nuclear deal Wednesday that would have sent its uranium stockpile abroad. The Obama administration is now under pressure to make good on its promises of 'consequences.'
The US is prepared to expand and toughen existing sanctions if Iran does not reverse course on its nuclear program.
All sides have promised to meet again. Israeli settlements and a belligerent Iran remain the biggest stumbling blocks.
Rolf Mowatt-Larssen, a former CIA counterterrorism expert, lays out his ideas on how to prevent the spread of nuclear materials on the black market – including the controversial 'Armageddon test.'
Consensus is rising in the international community: Enough cajoling, it's time to get tough.
But critics say the US should go slowly on a deal that would help a crucial trading partner for Iran.
It gingerly considers how to set consequences for Russia and maintain cooperation.