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, 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 Gates attended in Singapore, woke up the clutch of defense intellectuals and, for the most part, hardened views toward the regime. American officials said that countries at the conference, called the Shangri-La Dialogue, remained divided over whether North Korea was determined to develop nuclear weapons at any cost or could still be enticed to give them up. Gates, for one, signaled that the Obama administration had lost patience with the six-party talks aimed at persuading North Korea to abandon its nuclear dreams. 'Everyone in the room is familiar with the tactics that the North Koreans use,' he said with disdain in a question-and-answer session after formal remarks on Saturday. 'They create a crisis, and then the rest of us pay a price to return to the status quo ante. As the expression goes in the United States, I'm tired of buying the same horse twice.' At the same time, Pentagon officials admitted that they were largely in the dark about North Korea. 'I am constantly amazed by how little we know about what's going on in the North,' a senior Defense Department official said, acknowledging the difficult road ahead. 'If they are really totally crazy, how do you form a policy around that?' he said, speaking on the condition of anonymity. Gates' plane troubles were only slightly less mysterious. The problems began last Wednesday when a maintenance crew discovered that Gates' specially fitted 747, which had flown from Washington to pick him up at his high school reunion in Wichita, Kan., had developed a flap problem that prevented refueling in midair, a major timesaver. After five hours on the ground in Wichita, the problem was still not solved and the plane took off on a World War II-era island hop across the Pacific to Singapore, with refueling stops in Hawaii and Guam. Gates' planned 20-hour flight grew to 28 hours, forcing him to arrive too late for most of his Friday meetings. The aircraft, which is nicknamed the Doomsday Plane because it contains an airborne command center that can be used during an attack on the United States, was still under repair in Singapore on Sunday when the maintenance crew discovered a new hydraulic problem. Gates was grounded, he had planned to head that night to the Philippines and he was forced to truncate his schedule the next day in Manila. His staff described him as highly irritated by the Air Force, which as it happens has been angry about the defense secretary's proposed cuts to the F-22 fighter jet program. By Monday, the plane was fixed and Gates made it to Manila and then Alaska. 'Given the maintenance problems on my plane the last week, I'm really happy to be here with you today,' he told the crowd at Elmendorf Air Force Base outside Anchorage. 'I'm confident that there was absolutely no connection between those maintenance problems and my decisions on the Air Force budget.' Gates next headed north in Alaska on a military transport plane to Fort Greely. There, with an eye toward North Korea -- and critics of his proposed cuts to missile defense in Congress -- he descended into an underground silo, inspecting an interceptor missile that would theoretically stop an incoming warhead from North Korea and declaring that Americans were safe. What did he think of the interceptor up close? 'Forty years ago I was a lieutenant at an Air Force base that had Minuteman missiles,' replied Gates, who was in the last event on the last day of a very long trip. 'And, you know, a missile looks like a missile. You just make sure the pointy end is up.' 