Back in 1960, the CIA hatched a plan to kill Patrice Lumumba by infecting his toothbrush with a deadly disease. The Congolese leader would brush his teeth and, presto, in a few days or weeks he would be gone.

Around the same time, the CIA’s Health Alteration Committee — who thought that name up? — sent a monogrammed, poisoned handkerchief to Gen. Abdul Karim Kassem, the leader of Iraq.

And the CIA’s “executive action” unit plotted for years to murder Fidel Castro. It hired the Mafia to poison his food and tried to give him a diving suit contaminated with Madura foot, a rare tropical disease that starts in the foot and moves upward, slowly destroying the body. The CIA also considered offing the Cuban leader with an exploding cigar, a poison pen, and a seashell that would blow up underwater when he touched it.

Not one of the plots was successful. Lumumba and Kassem were executed by their foes, and Castro is still alive. But the plots make clear that the CIA has been licensed to kill for decades.

Congress — especially congressional Democrats — was outraged earlier this month when it was disclosed that, apparently on orders from Vice President Dick Cheney, the CIA for eight years concealed from Congress a program to assassinate the leaders of Al Qaeda, starting with Osama bin Laden. But they shouldn’t have been surprised that such a plan was being hatched.

The CIA’s involvement in planning assassinations goes back at least to 1954, when it prepared a manual for killings as part of a U.S.-run coup against the leftist government of Guatemala. The 19-page manual, which was declassified in 1997, makes chilling reading. “The essential point of assassination is the death of the subject,” it declares, noting that although it “is possible to kill a man with the bare hands … the simplest local tools are often much the most efficient means of assassination. A hammer, ax, wrench, screwdriver, fire poker, kitchen knife, lamp stand, or anything hard, heavy, and handy will suffice.”

The agency’s manual recommends “the contrived accident” as the best way to dispose of someone. “The most efficient accident … is a fall of 75 feet or more onto a hard surface. Elevator shafts, stairwells, unscreened windows, and bridges will serve.” The manual suggests grabbing the victim by the ankles and “tipping the subject over the edge. … Falls before trains or subway cars are usually effective but require exact timing.”

The manual goes on to discuss “blunt weapons,” noting that “a hammer can be picked up almost anywhere in the world” and that baseball bats are also excellent. The manual explains the best place in the body to stab people or how to bash their skulls in and the pros and cons of rifles, pistols, submachine guns, and other weapons.

During the Cold War years, the CIA plotted against eight foreign leaders, five of whom died violently. The agency’s role varied in each case.

After the plots were publicized by a Senate committee, President Gerald Ford issued an executive order in 1976 barring political assassination. President Ronald Reagan broadened the ban, dropping the word “political” and extending the prohibition to include contract killers as well as government employees.

Although the ban remains in effect, it largely has been ignored on the premise that it does not apply in a military setting. Consider the following:

In 1986, Reagan ordered the bombing of Libya in retaliation for a terrorist attack on a Berlin disco that killed three people, including two U.S. servicemen, and wounded more than 200 others. In the air strike, Libya’s leader, Moammar Gadhafi, a target of the raid, escaped unharmed, but his 2-year-old adopted daughter was killed.

The problem with assassination, morality aside, is that the U.S. is not very good at it, as the CIA’s farcical efforts to murder Castro demonstrate. It seems unlikely that the CIA will kill Bin Laden with a baseball bat. And there is the real possibility of retaliation for a state-sponsored assassination. President John Kennedy was quoted as saying, “We can’t get into that kind of thing or we would all be targets.”

Perhaps CIA Director Leon Panetta had that in mind when he canceled the assassination program.