Washington ? During a meeting on North Korea in late 2001, John R. Bolton’s repeated talk of overthrowing Kim Jung Il frustrated the State Department’s specialist on the country. “Regime change” is not President Bush’s declared objective in North Korea, Charles L. Pritchard recalled telling Bolton, the undersecretary of state for arms control and international security.

“That is exactly what we are all about,” Bolton snapped back, curtly reminding Pritchard and a colleague that U.S. troops had just finished overthrowing the Taliban in Afghanistan, according to Pritchard.

For the last four years, as the administration’s point man on weapons of mass destruction, Bolton has worked to reverse decades of U.S. nonproliferation and arms control policies.

His record, including allegations that he used unconfirmed intelligence to promote his policy goals, will be the focus of Senate confirmation hearings starting today. Bush has nominated Bolton as ambassador to the United Nations, an organization he has described as irrelevant.

Participants expect the hearings to be combative, and to include allegations by Bolton’s critics that he misused intelligence data to support his goals, verbally abused subordinates and helped allies in other agencies defeat the proposals of his State Department superiors.