In the months Nixon had spent trying to get Thieu to sign the Paris Accords, he sent letter after letter promising to “respond with full force should the settlement be violated by North Vietnam,” to “insure that the provisions of a peace settlement are strictly enforced,” to “take swift and severe retaliatory action.”1 South Vietnam’s president didn’t buy it. As an NSC aide reported to Kissinger on December 20, 1972, Thieu argued that “it would not be possible for the US to retaliate against North Vietnam if the Kissinger/Tho agreement were violated, since the US would not risk having new POWs.”2 Why would Thieu say this during the Christmas bombing, which gave Hanoi a chance to shoot down fifteen B-52s and capture twenty-four new prisoners?3
There was a world of difference between bombing the North before the Paris Accords and bombing it afterward. Before, Nixon had something to trade for the release of the POWs: total American withdrawal. The Accords, however, removed all American troops from Vietnam in return for the POWs. Under the Accords’ terms, both the troops and the POWs exited Vietnam during February and March 1973. That meant that as of April 1, 1973, Nixon could not send American bombers back over North Vietnam without putting himself in a military, diplomatic, and political bind. What would he do when Hanoi shot down a plane and took its crew prisoner? How could he free them then? He couldn’t count on a daring commando raid to rescue them. He’d tried that at Son Tay in 1970 and found an empty prison. He couldn’t offer total withdrawal of American ground troops again; Hanoi already had that. No matter how he spun the Christmas bombing to the public, he knew he couldn’t force Hanoi to release the POWs by bombing it more; that was how Hanoi got prisoners. Nixon could offer to stop bombing in return for the POWs’ release, but then he’d be accused of surrendering. It wouldn’t be the subtle, concealed surrender of a “decent interval,” but the open, public, undeniable kind.
Or he could just keep bombing. If NSSM-1 was right, and Saigon couldn’t survive without American troops on the ground, then Nixon would get the POWs back after the North conquered the South. But in that case, he’d have to share responsibility for military defeat. If NSSM-1 was wrong, and American airpower was enough to keep Saigon going—even without American advisers there to get South Vietnamese soldiers to hold their ground and create “lucrative targets” out of North Vietnamese troops, or to direct the bombing thereof—then the POWs would remain in Hanoi for as long as Hanoi kept fighting. If Nixon had bombed the North after April 1973, his options would shrink to surrender, defeat, or letting the POWs rot indefinitely.
That was the military and part of the political dilemma that bombing would have posed for him. The diplomatic dilemma had scandal potential. Nixon got the North Vietnamese to sign the Paris Accords in the first place by giving Moscow and Beijing secret assurances that they could violate it. Through Kissinger, he had let Hanoi’s biggest allies know that as long as it waited a year or two before taking over the South, he would not intervene. In other words, he would not enforce the agreement. It was with this understanding that China and the Soviet Union had used their influence to encourage Hanoi to sign. Obviously, bombing the North would have risked the relationships Nixon had created with the Soviets and Chinese. Less obviously, it would have risked public exposure. He and Kissinger both assumed the Communists taped their closed-door meetings. If Nixon had intervened following the settlement, Moscow or Beijing could have responded by playing tapes of Kissinger telling them he wasn’t going do that. A diplomatic problem would then have risked becoming an additional political debacle.
In February and March 1973, while the Paris Accords were still bringing the troops and POWs home, Nixon said in the Oval Office on more than one occasion that he would not be able to bomb the North. He even said it to a newly freed prisoner visiting him on March 12, Captain Jeremiah Denton. It came up in a discussion of reconstruction aid. Nixon was trying to enlist POW support for providing American aid to Hanoi, an idea that was growing more unpopular as the prisoners revealed more details of their suffering. “Aid is a tool that we can use,” Nixon said. “We might restrain them. I’m not sure. They’re savages, they’re barbarians, they’re terrible people, they’re primitive and all that.” But if they violated the agreement, America could cut off aid.
“If we don’t have this tool, what other tool do we have? Well, we can threaten, look, we’ll bomb you again,” said the president. “But that’s an idle threat. It’s not totally idle, because they think I’m a little, shall we say, crazy.”4 Nixon didn’t explain why the threat was idle—or why Hanoi would have to succumb to Madman Theory to take it seriously.5 With British prime minister Edward R. G. Heath on February 1, Nixon made a similar point: “Henry’s got them [the North Vietnamese] convinced there’s a madman in the White House who doesn’t care about polls or anything and might bomb you again.”6
If sending the B-52s back in would be a self-destructive, even irrational, act for Nixon, failing to do so would be risky as well. It would leave him open to the charge of abandoning an ally, failing to keep a promise (Thieu could make Nixon’s letters public, and eventually did), and snatching defeat from the jaws of victory. He’d convinced majorities that the May 8 and Christmas bombings succeeded; how could he justify not defending the South with American airpower?