MINOT, N.D. -- Hours after being named President-elect Barack Obama's choice to remain as defense secretary, Robert Gates visited Minot Air Force Base and said lapses in nuclear weapons procedures last year were unacceptable.

Gates on Monday became the first defense secretary to visit the Minot base. He stopped first in Chicago, where Obama announced he had asked the 65-year-old Pentagon chief to remain at his post.

Gates said it was not his "expectation or desire" to stay on the job, but he was persuaded to "serve a little while longer." He said he feels honored to work under Obama, who will be the eighth president he has served.

The Minot base drew attention last year when nuclear cruise missiles were mistakenly loaded onto a B-52 bomber and flown to Louisiana. The incident was cited by Gates as one factor leading to the ouster of the Air Force's chief of staff and its secretary. About 65 airmen at the Minot base were sanctioned.

Gates, speaking to the airmen in a B-52 hangar, said the missteps stemmed from a "long-standing slide of nuclear stewardship" that did not get the attention, personnel or funding it deserved.

Now, he said, more emphasis on the nuclear program is moving it in the right direction. "You must never take your duties lightly," he told the airmen. "There is simply no room for error."

The Minot bomb wing commander, Col. Joel Westa, called the Minot base a strategic prairie outpost. He told Gates, "I'm convinced when you leave here, you'll be able to rest comfortably."