UNITED NATIONS — The reception for James Cunningham was supposed to be a celebration.
Cunningham, the U.S. deputy ambassador to the U.N., had been nominated for a high-profile job in Vienna, helping control the spread of weapons of mass destruction. He had been approved by the Senate Foreign Relations Committee and was waiting for the Senate to sign off, usually a mere formality.
But as Cunningham greeted well-wishers at the U.N. farewell party, it was clear that he was not celebrating.
"I haven't been confirmed yet," Cunningham told one ambassador, his famous poker face betraying a trace of dismay. "The nomination is on hold."
Instead of going to Vienna as the U.S. representative to the International Atomic Energy Agency, Cunningham was headed to limbo.
The obscure congressional device called a "hold" started as a courtesy for senators who couldn't be present for a vote or had a question about a nomination. Senators welcome it as an additional bit of leverage for scrutinizing candidates or pushing reform. But it is more often used as a political tool to wring concessions from an administration on a pet issue -- often unrelated to the nominee -- that can delay an appointment for months or even scuttle it.
Senators don't have to publicly reveal the reason behind the hold, or even say that they have placed one. In Cunningham's case, Republican Sens. Jon Kyl of Arizona and James M. Inhofe of Oklahoma lodged a "secret" hold to force the White House to reject the Comprehensive Test Ban Treaty and devise a new nuclear nonproliferation strategy, State Department officials said.
Kyl and his staff did not respond to more than a dozen phone calls to his offices in Washington, Tucson and Phoenix over a week requesting comment. Inhofe's spokesman did not reply either. But two senior U.S. officials who asked not to be named said that even after Secretary of State Colin L. Powell intervened, Kyl would not release the hold.
During the confirmation hearing in June, Sen. Richard G. Lugar (R-Ind.), the chairman of the Foreign Relations Committee, praised Cunningham's "extensive experience" and "substantial abilities" and emphasized that the post was a significant one.
"If confirmed, Ambassador Cunningham would take his seat at the IAEA at a critical time for United States nonproliferation objectives, particularly in light of activities by North Korea and Iran," Lugar said.
Committee staffers on both the Republican and Democratic sides said the hold had nothing to do with Cunningham's qualifications or position.
Because the Senate is in recess until Sept. 7, the top post in Vienna will remain unfilled while the U.S. tries to guide action on Iran's and North Korea's nuclear programs at a key IAEA meeting next month. But the delay affects more than policy.
Often forgotten in the political maneuvering is the person caught in the middle -- in this case, a career diplomat who has served six presidents in 29 years and who handled critical negotiations on Iraq and nonproliferation while at the U.N.
Because he can't tell how long the hold will last, Cunningham doesn't know where his family should live, or where his teenage daughters should enroll in school. His U.N. job and New York apartment are taken, his house in Washington is rented to someone else, and he can't move to Vienna until he is confirmed.
G. Calvin Mackenzie, a professor of government at Colby College in Maine who has extensively studied the nomination process, said that the holds -- which can be placed on judicial, military or diplomatic appointments -- have numerous negative consequences.
They undermine policy, discourage candidates and destroy morale, especially among career officers, he said.
"It's hard to have a coherent foreign policy when the president can't deploy the people to carry it out," Mackenzie said.
Anthony Lake faced a hold on his nomination as CIA director in 1997 and eventually withdrew his candidacy. He described the experience as being a "political football in a game with constantly moving goal posts."
But the holds allow senators to garner attention for favorite issues.
"More and more senators are using them without shame, because they have learned how a hold can be quite potent politically," said Paul Light, a New York University professor of public service who has been tracking the appointments process for 20 years.
"I can't think of a single example during the Bush administration where a hold was used to stop a nominee who was thought to be unqualified for office," Light said. "It is now used to make political points in a visible way."
Senators who have used the holds defend their value. Sen. Hillary Rodham Clinton (D-N.Y.) placed a hold on the nomination of the new director of the Environmental Protection Agency in the spring to protest the agency's monitoring of air quality in New York after 9/11. Sen. John McCain (R-Ariz.) put a blanket hold on all military promotions in 2002 to castigate the Defense Department for not consulting sufficiently with the Senate.