"I've spent my entire adult life with the United States as a superpower, and one that had no compunction about spending what it took to sustain that position," he told Newsweek.
"It didn't have to look over its shoulder because our economy was so strong. This is a different time," he said. He said that it was one of reasons behind his decision to step down.
"To tell you the truth, that's one of the many reasons it's time for me to retire, because frankly I can't imagine being part of a nation, part of a government that's being forced to dramatically scale back our engagement with the rest of the world," he said.
Gates, who'll be succeeded by Central Investigation Agency chief Leon Panetta, served in both the Bush as well as Obama administration. He said he had not been in favour of using ground troops to kill Osama bin Laden and preferred air strikes.
"I was very explicit with the president in one of the discussions," Gates acknowledged. "I said, 'Mr President, I want truth in lending. Because of experience, I may be too cautious, you know.'"
Gates also spoke about how he had reached out to US Secretary of State Hillary Clinton. "I just told her, based on my experience, the administration worked would depend a lot on how well she and I got along together," Gates recalled.
"If we got along, the message would go to the entire bureaucracy not just our own bureaucracies but the rest of government as well. She totally understood," he added.
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