As Liberalpragmatist pointed out, Fred Thompson, former GOP senator fromTennessee, is a more serious presidential candidate than one might guess based on his acting career. Why not? His roots in the Republican culture of cover-ups run deeper than his current work on behalf of Scooter Libby.
As I was researching the Moorer-Radford Affair for a forthcoming book, I came across Thompson. What's the Moorer-Radford Affair? A Nixon-era espionage ring so creepy it spooked Nixon. Admiral Thomas Moorer, Chairman of the Joint Chiefs of Staff, became convinced in 1970 that Nixon was selling out the U.S. to "Red China," so he authorized a young sailor assigned as an aide to the National Security Council to begin spying on Kissinger -- actually stealing documents. When Nixon found out in 1971, he called it "a federal offense of the highest order" (something about which he knew a thing or two), and considered prosecuting Moorer for treason. Instead, he decided to cover-up, persuaded by Kissinger that thereafter Moorer would be in his debt, a weakened Chairman of the Joint Chiefs who'd more willingly conform to Nixon's wishes.
Who helped him cover it up? That's right -- Fred Thompson. Here's a short bit from James Rosen's 2002 Atlantic Monthly feature, "Nixon and the Chiefs" (subscriber only):
A previously unpublished Senate Watergate committee memorandum, dated December 5, 1973, and addressed to Fred Thompson, the committee's minority counsel (now a U.S. senator from Tennessee), noted that the investigation of Radford had turned up "another person on the NSC staff who was helping" him, named David Oscar Bowles. Like Radford, Bowles was swiftly transferred—to Corpus Christi. But unlike Radford, Bowles has never spoken on the record about his role in the military espionage; indeed, until now his alleged involvement in the Moorer-Radford affair has never been publicly disclosed.
To be fair, Thompson played only a minor role (same as his acting career), and he did do some honest work in the Watergate investigation. And, for all I know (Rosen doesn't go into it), maybe Thompson was shocked, just shocked at such shenanigans, though the Moorer-Radford Affair did not become public knowledge for some time after that. Either way, this is nothing but a footnote to history, a minor detail in the life of an unimportant man. Let's hope it becomes nothing more.