US President Barack Obama on Monday cited the courage of Joplin residents as an inspiration for the rest of the country nearly one year after a powerful tornado killed 161 people in this Midwestern town.

The twister, a massive funnel cloud that struck on May 22, ranked as one of the deadliest tornado to hit the United States since 1947.

Obama traveled to the town of 50,000 to talk to students graduating from Joplin High School following two days meeting with world leaders at the NATO summit in Chicago.

"My deepest hope for all of you is that as you begin this new chapter in your life, you will bring that spirit of Joplin to every place you travel and everything you do," Obama told the students.

"You can serve as a reminder that we're not meant to walk this road alone; that we're not expected to face down adversity by ourselves. We need each other. We're important to each other and we're stronger together than we are on our own."

It is this spirit "that's allowing all of you to rebuild this city. That's the same spirit we need right now to help rebuild America," he said.

The United States "will only succeed if we all pitch in and pull together -- and I'm counting on you to be leaders in that effort," he told the students.

Obama visited Joplin in late May 2011 after the devastating tornado blew through the town and promised residents to stand by them "every step of the way."

More than 8,000 structures in the town, including a major commercial area, were damaged or destroyed when the tornado packing winds over 200 miles (320 kilometers) per hour came roaring through with just a 24-minute warning.