Perhaps this is being too simplistic in regards to foreign policy, but one of the reasons the United States has always been regarded as a dealmaker is because it keeps its word.
And because we have that stellar reputation, it tends to raise the bar in the bargaining process.
All that hard-earned respect took a hit Tuesday when President Trump pulled the United States out of a deal made between five other nations Britain, China, France, Germany and Russia to keep Iran from producing nuclear-grade weaponry.