Back in 1990, Congress passed the Americans with Disabilities Act to protect handicapped people. It was a human rights advance, guaranteeing that impaired or wheelchair-bound folks cannot be excluded from the mainstream of daily life. Public facilities must accommodate them.

Later, the United Nations drafted a global treaty to extend this protection worldwide. Compassionate leaders everywhere saw the moral correctness of the plan, and 126 nations ratified it.

When the U.N. treaty came before the U.S. Senate for ratification Tuesday, it was endorsed by Republicans like Sen. John McCain and former President George H.W. Bush. In a wheelchair, aging GOP Sen. Bob Dole returned to the chamber floor to back the treaty. The GOP supporters said it would protect disabled U.S. veterans who travel abroad.

But far-right tea party Republicans -- who absurdly think the United Nations threatens American "sovereignty" -- killed it. They lined up in lockstep to prevent the required two-thirds approval. Sen. Mike Lee, R-Utah, called one treaty clause "part of a march toward socialism."

The defeat was a grotesque display of gridlock, in which an out-of-step minority blocked humane efforts of the majority.

The floor manager for the treaty, Sen. John Kerry, D-Mass., lamented:

"This is one of the saddest days I've seen in almost 28 years in the Senate, and it needs to be a wakeup call about a broken institution that's letting down the American people .... Today, the dysfunction hurts veterans and the disabled, and that's unacceptable. This treaty was supported by every veterans group in America, and Bob Dole made an inspiring and courageous personal journey back to the Senate to fight for it. It had bipartisan support, and it had the facts on its side, and yet for one ugly vote, none of that seemed to matter."

Writing in U.S. News & World Report, Susan Milligan said the outcome "damaged America's moral authority in foreign affairs." She said the treaty was defeated "because of the misguided paranoia of a conservative minority."

West Virginia's Sen. Joe Manchin told reporter Paul Nyden that ultraconservative senators "think the United Nations is the bogeyman .... I thought it was a shame to use scare tactics."

Americans share the world with other societies, and should cooperate, Manchin said. "We are all on the great planet Earth together." He added that the treaty merely "asks that the world community treat people with the same dignity and compassion that we treat people with disabilities here in the United States."

The Kansas City Star said: "Opposition to the treaty was drummed up by far-right denizens like Rick Santorum and Glen Beck, who claimed it would empower governments to tell parents how to care for disabled children. Other groups said it was really a call for more abortions. None of that is true."

The BaltimoreSun said the defeat was caused by "the paranoid wing of the Republican Party, with its history of offering visions of black helicopters and storm troopers whenever the subject of the United Nations comes up."