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As Barack Obama's first year in office comes to a close, grumbling about his alleged shortcomings has become a favorite pastime among liberals. The reality, however, is that a president's room to move on most policy areas is severely constrained by the realities of congressional politics. The major exception to this is foreign policy. Here political constraints are much looser, and it's a good deal fairer to hold the White House responsible for outcomes. And the results have been fairly impressive. Obama may not have reimagined America's role in the world, but he has slowed the deterioration in American influence that had been underway since the 2003 invasion of Iraq.

Ironically, the quality that's helping Obama here is the very thing that's tended to annoy liberals when it...