What is the meaning of "you would think that someone had beat me to it”?

Question

The following is a sentence from the article Paging Dr. Carson of The New Yorker:

Carson mentioned that operation in the first Republican Presidential debate, last month. “I’m the only one to separate Siamese twins,” he said. “The only one to take out half of a brain, although you would think, if you go to Washington, that someone had beat me to it.” It was a Carson shot.

I cannot understand the meaning of the second sentence in bold type. I would be grateful if someone could help me understand it.

Answer 1

Ignore the break in the middle for he said, and this is the full quote:

“I’m the only one to separate Siamese twins, the only one to take out half of a brain, although you would think, if you go to Washington, that someone had beat me to it.”

Dr. Carson launches his sentence with a description of his most famous achievement:

I'm the only one to separate Siamese twins

He then narrows this description by focusing on the most delicate and difficult piece of it:

[I'm] the only one to take out half of a brain

Note that he recasts what he actually did—separating two physiologically conjoined brains—as dividing one brain into two halves and taking one away, leaving only half a brain. This sets up his joke:

you would think, if you go to Washington, that someone had beat me to it.

Examining people in "Washington" (that is, people in the government) would lead you to think that "somebody beat me to it" (that is, somebody achieved the medical feat of removing half a brain before I did)—because people in the government obviously have only half a brain left!