As they say, you don't really know someone until you've traveled with them.

Rep. Adam Smith, based on his years and friendship with House Armed Services Chairman Rep. Mac Thornberry, R-Texas, said the upcoming acquisition reform negotiation between Thornberry and Senate Armed Services Chairman Sen. John McCain, R-Ariz., "is going to be one of the more fascinating things for me to watch."

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The reform proposals in both chambers are championed by their new chairmen, "two men who could not possibly have two more different personalities," the Washington-based Democrat said.

Smith and Thornberry have served together on the House defense committee for years. When Democrats were in control, Smith was chairman of the terrorism subcommittee and Thornberry was his ranking member, and the pair spent a lot of time traveling the globe together.

"Mac is the most thoughtful, quiet, calm guy I think I've ever seen in Congress," he said.

In their travels for the subcommittee, "we'd sit on one of those G5s [business jets] across from each other and I swear if I hadn't engaged we could have gone 11 hours without saying a word. And that not meant in a bad way — Mac likes me. ... He's just contained where he's at."

On the other hand, Smith said, "I can't picture John McCain getting to the end of the tarmac without having something to say."