ANCHORAGE  Defense Secretary Robert M. Gates runs the most powerful military in the world, but his six-day trip to Asia and Alaska this past week proved how much remains out of his control.

Not only did he have to respond to the unpredictable nuclear theatrics of North Korea  a country senior Defense Department officials routinely describe as not of this planet  but he also was grounded by days of repairs to his plane, which is built to withstand a nuclear blast but not, it turns out, a broken wing flap.

From the top of a hotel crammed with Asian generals in a steamy Singapore to the bottom of a missile silo in sub-Arctic Alaska, Mr. Gates took a tough line in public on North Korea and a tough line in private on the Air Force, which provides the maintenance crew for his plane. In both cases, senior defense officials said it was hard to know what was actually going on.

North Korea, of course, presented the greater strategic implications. Its nuclear test on May 25, days before the major security conference that Mr. Gates attended in Singapore, woke up the clutch of defense intellectuals and, for the most part, hardened views toward the regime.