In 1969, North Korea shot down a US spy aircraft over the Sea of Japan (East Sea), killing the 31 personnel on board.Frankly, I don't know very much about the 1969 downing of that plane, but it has echoes of the sinking of the Chonan (or is that the other way around?). Here and there in the K-blogosphere I have read claims that the US would have reacted far more harshly than ROK President Lee Myungbak's lack of attack, but when we see the hypothetical as a real situation, that doesn't seem to be the case. At least not four decades ago.
Despite US outrage, the new Nixon administration chose not to retaliate other than to order a continuation of flights and go ahead with naval exercises.
The documents, released after requests under the Freedom of Information Act, showed that the administration nonetheless charted out a series of options that included conventional and nuclear attacks.
In one contingency plan codenamed "Freedom Drop," the United States would use tactical nuclear weapons to destroy military command centers, airfields and naval bases in North Korea.
Civilian casualties "would range from approximately 100 to several thousand," said a classified memorandum by then-defense secretary Melvin Laird prepared for Henry Kissinger, who was Nixon's national security adviser.
There is no indication that the administration seriously considered a nuclear strike. The document stated that the United States could use one nuclear option if North Korea launched an air attack on the South.
Of course, the US was fighting a major war a few thousand miles southwest of the Korean Peninsula, which may have affected things. Oh, wait.