While holding a speech at the U.S. Naval Academy, an institution he attended long ago, Republican presidential candidate John McCain promoted the duties of citizenship and urged Americans to engage in public service.

"If you find fault with our country, make it a better one," McCain said before the crowd.

McCain called on young Americans to consider getting more involved in the public service, including military service.

"When healthy skepticism sours into corrosive cynicism, our expectations of our government become reduced to the delivery of services," McCain said.

The Arizona senator then talked about what he learned while attending the U.S. Naval Academy. The most important lesson was to sustain his self-respect so that he could serve something greater then himself, the Republican said.

McCain said that being a good citizen of the United States means more than walking into a voting booth every two or four years.

He talked about his years spent at the Naval Academy and that the lessons learned there, although that happened without his knowledge, had helped him in crisis situations.

"In a later crisis, I would suffer a genuine attack on my dignity - an attack … that left me desperate and uncertain," McCain said probably referring to the period of his life when he was taken prisoner in the Vietnam War.

"It was then I would recall, awakened by the example of men who shared my circumstances, the lesson that the academy in its venerable and enduring way had labored to impress upon me," McCain said.

The 71-year-old Arizona senator also announced the fact that his staff had begun looking for potential vice presidential nominees. He said he hopes to make a selection before the Republican convention in early September.

The republican mentioned some potential candidates. The list includes Tim Pawlenty of Minnesota, Charlie Crist of Florida, Jon Huntsman Jr. of Utah and Mark Sanford of South Carolina.