Any suspicion that the political right, after suffering a defeat on the debt ceiling and facing threats from business donors, is losing its clout can be dismissed by the fight over the United Nations Convention on the Rights of Persons with Disabilities.

The treaty has been ratified by 141 countries. It is backed by the White House, former President George H.W. Bush, the major U.S. disability and veterans advocacy groups, and American businesses.

Senate Republicans, however, already defeated the treaty in 2012, and it now faces an uphill slog to get the two-thirds vote needed for ratification. Right-wing critics, led by former Senator Rick Santorum, the Heritage Foundation and home-schoolers, charge that adopting it would allow global enforcers to dictate the treatment of Americans with disabilities or the permissibility of home schooling, and ease access to abortion.

In reality, the treaty is modeled on the Americans With Disabilities Act of 1990. It states that nations must ensure that people with disabilities get the same rights and are treated with same dignity as all others. It might well pressure other countries to adopt U.S. standards.

Proponents say American leadership is important, a demonstration of the soft power of ideals and values. If passage emboldens other nations to elevate their standards, it will make life easier for Americans with disabilities, including veterans, when traveling outside the U.S.

Despite strong opposition from Senate Republicans, led by Tennessee's Bob Corker, the treaty has a distinctively Republican flavor. The Americans With Disabilities Act was the signature domestic achievement of George H.W. Bush's presidency, and the UN treaty was negotiated by his son's administration. The most important champion is former Senate Republican leader Bob Dole, a disabled World War II veteran; it is supported by another former party leader, Bill Frist, a physician.

Its chief backers in the current Senate are John Barrasso of Wyoming, another physician who is one of the most conservative members of the chamber, and John McCain of Arizona, a disabled veteran.

Veterans' organizations backing the treaty include the American Legion, the Veterans of Foreign Wars, the Iraq and Afghanistan Veterans of America, and the Wounded Warrior Project. It is embraced by the U.S. Chamber of Commerce and major companies such as AT&T Inc., Wal-Mart Stores Inc., Coca-Cola Co., Nike Inc. and International Business Machines Corp.

The opposition from Santorum, Heritage, a slice of the home-schooling movement and a few right-wing Catholic organizations seems, on the surface, a mismatch. Yet these groups are very vocal, and they capitalize on many Republicans' fears of challenges from the right. The disabilities community isn't that well organized, nor does it rank among the big campaign contributors.

Corker says his opposition is based solely on the dangers the treaty poses to national sovereignty and the threat that it will supersede U.S. law and states' rights. He cites a 1920 Supreme Court ruling on a migratory-bird treaty as precedent. Under the Tennessee Republican's reasoning, the U.S. couldn't join any treaty involving human rights, civil rights, gay rights or disability rights.

In the Senate, supporters are writing in "reservations, understandings and declarations," attesting that nothing in the treaty affects current U.S. law. This is a common practice, the Economist magazine notes, for treaties ratified by the U.S. and other countries.

It makes the Corker argument specious, says Richard Thornburgh, who was attorney general during George H.W. Bush's administration and is an advocate for the treaty.

"These reservations attached to a treaty are part of the treaty," he says. "There is nothing in this treaty that would allow what critics allege."

Dole, who showed up in his wheelchair in 2012 to lobby (unsuccessfully) for the pact, says that ratification is such an easy call that when he ran the Senate, it "would have passed by voice vote." He remains optimistic that it will pass this time, though he says he is worried because "a few senators aren't returning my calls."

There probably are 61 votes for the treaty. That number includes all the Senate Democrats plus six Republicans: McCain, Barrasso, New Hampshire's Kelly Ayotte, Lisa Murkowksi of Alaska, Susan Collins of Maine and Mark Kirk of Illinois, who is disabled after suffering a stroke.

It needs six more Republicans to pass. The targets are the two senators from Tennessee -- Corker, a thoroughly decent man and good lawmaker who has come to a dubious conclusion, and Lamar Alexander, who really isn't threatened by his right-wing primary challenger; the senators from Dole's Kansas, Jerry Moran and Pat Roberts, who is scared stiff of his conservative challenger; and those from non-right-wing states such as Ohio's Rob Portman, who is closer to the Bush family than any other lawmaker, and Pennsylvania's Pat Toomey. Mike Enzi, who no longer faces a challenge from Dick Cheney's daughter, could join Barrasso, his Wyoming colleague; Georgia's Saxby Chambliss and Johnny Isakson have shown an admirable willingness to break with right-wing zealotry.

Supporters may not get any of these votes, which Tim Shriver, the chairman of the Special Olympics, finds astounding.

"What values here do these opponents not believe in?" he asks. "This treaty brings to the table a place where America is the shining light on the hill."

(Albert R. Hunt is a Bloomberg View columnist.)

To contact the writer of this column:

Al Hunt in Washington at +1-202-654-4306 or

ahunt1@bloomberg.net.

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