WASHINGTON (AP) _ House leaders were right not to let military action against Iraq divert them from the impeachment proceedings against President Clinton, says a Republican lawmaker who was a prisoner of war in Vietnam when members considered the fate of Richard Nixon.

In the weekly GOP radio address, Texas Rep. Sam Johnson today urged Congress not to let Saddam Hussein dictate ``when we will carry out our duty to defend and uphold the Constitution.''

Johnson, who served 29 years in the Air Force, was a prisoner of war for nearly seven years in Vietnam. During his time in captivity _ three of which were in solitary confinement _ Congress debated President Nixon's fate. Johnson said the proceedings showed him that America still believed in the ideals for which he was fighting.

``I knew in Vietnam that I was defending my nation and its proud tradition of freedom and the rule of law,'' Johnson said. ``And I was proud that our democratic tradition was carrying out, unimpeded by the circumstances of the day.''

Some members of Congress warned impeachment proceedings during the strike against Iraq could damage troop morale. But Johnson, both in the address today and on the House floor Friday, said Congress must carry out its duty with the same resolve as the troops in their mission in Iraq.

``The men and women in the Persian Gulf are conducting a mission to fight tyranny abroad. And we must support them by protecting the constitutional foundations of our democracy at home.''