Presidential candidate Michael Dukakis, defending his military policies, dismisses as "nonsense" the contention by Vice President George Bush that his Democratic approach amounts to unilateral disarmament.

At the same time, brushing aside support by his own running mate for new aid to the Nicaraguan Contra rebels, Dukakis would like to turn a table on Bush by pledging "this fiasco in Central America is going to end" if the Republican Party is turned out of the White House.The comments came on the first day of Dukakis's three-day campaign trip that Friday was to take him outside Los Angeles to Laguna Beach and then onward to Seattle before wrapping up Saturday in Denver and in Cedar Rapids, Iowa.

The Democrat was responding to a strongly worded speech by Bush Thursday in Corpus Christi, Texas, in which the vice president charged that Dukakis would forfeit America's role as a world leader if elected and would turn his back on 40 years of U.S. foreign policy experience.

"His positions, if taken together, add up to a major departure from the post-war bipartisan consensus on foreign policy," said Bush, a former CIA director, envoy to China and U.N. ambassador who has frequently attacked the Massachusetts governor for being too inexperienced in global affairs.

"In my judgment," Bush told the American GI Forum, a mostly Hispanic veterans group, "they amount to a rejection of America's role as a world leader and a repudiation of the Truman Doctrine and the vision of John F. Kennedy."

Invoking the words of President Kennedy on the need to "oppose any foe to assure the survival and the success of liberty" was a particularly biting reference because Dukakis often compares himself to his fellow Bostonian.