"I disagree with voices in my own party who argue we should not engage at all, who warn we should heed the words of John Quincy Adams not to go 'abroad, in search of monsters to destroy,'" he said.
Near the end of his address, Rubio, who was reading his speech from papers on the lectern, paused and looked around.
"I left the last page of my speech," he said, flipping through the papers and looking to Lieberman for some help. "Does anyone have my last page?"
A man on the stage handed him the page, and Rubio went on to finish his address, quoting former British Prime Minister Tony Blair about how interventionism is part of America's "destiny."
"This is why I need this page," he said smiling, adding later: "I couldn't memorize a Tony Blair quote."
After the event, Lieberman offered some advice for the vice presidential contenders before getting into the car that would take him back to Capitol Hill.
"Continue to be who you are," he advised. "Really. And history—fate will work its will."
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