Iran war forces America to confront the strategic cost of deterring China

The most strategically revealing military move in the Iran war this week isn’t another strike on Tehran. It is an American aircraft carrier leaving the Pacific. The USS George Washington is heading toward the Middle East to relieve the USS Abraham Lincoln, whose overall deployment has exceeded 260 days, including more than 240 uninterrupted days at sea. The move could leave the Pacific without a U.S. carrier for an unknown period.

That does not mean China is preparing to attack Taiwan. It...