Granted, if you're the governor of a state, it is a little strange to disappear for almost a week without telling your staff your whereabouts or setting up any kind of contingency planning. As South Carolina's The State reports:

S.C. Gov. Mark Sanford arrived in the Hartsfield-Jackson International Airport this morning, having wrapped up a seven-day visit to Buenos Aires, Argentina, he said. Sanford said he had not been hiking along the Appalachian Trail, as his staff said in a Tuesday statement to the media.

Sanford's whereabouts had been unknown since Thursday, and the mystery surrounding his absence fueled speculation about where he had been and who's in charge in his absence. His emergence Wednesday ended the mystery. ...

Sanford said he was alone on the trip. He declined to give any additional details about what he did other than to say he drove along the coastline.

Still, I'd argue that it's even stranger that an unplanned sojourn to Buenos Aires can ruin your presidential chances but not, you know, something truly insane, like trying to turn down $700 million in stimulus money during the deepest recession since the 1930s. 

P.S. Jonathan Martin has this precious nugget in his how-strange-is-too-strange piece about Sanford and presidential politics: 

Ed Rollins, who ran Perot’s ill-fated 1992 campaign for a time, recalled a conversation he had with the late Hamilton Jordan, another top strategist working for the Texas billionaire, after the two came to the conclusion that their candidate had no business controlling nuclear warheads.

Jordan, Rollins said, was worried that Perot might win.

“There is no way he is going to end up being president,” Rollins said he told Jordan. “This guy is nuts, and the country will find that out.”

Hmm. Not exactly an advertisement for hiring Ed Rollins. I wonder if he was having these sorts of conversations while advising Mike Huckabee last year.

Update: ABC (via Yglesias) has this intriguing--but not exactly surprising--wrinkle:

ABC’s Joe Goldman reports that a US embassy official in Buenos Aires tells him that the embassy had “absolutely no idea” that Sanford was in Argentina. The embassy official added that this comes "from out of left field -- it would be extremely odd that a US governor would not check in with the embassy."

Second Update: On the NYT site right now:

Breaking News 2:32 PM ET:

Gov. Mark Sanford of South Carolina Admits an Affair and Apologizes to Family

I guess that settles it. I still say it shouldn't be nearly as disqualifying as turning down badly needed stimulus money. An affair is wrong but understandable. Turning down the money is wrong and bats**t crazy.

--Noam Scheiber