HOUSTON--Former President Ronald W. Reagan took center stage tonight with a comprehensive defense of the last 12 years of Republican rule, as the Grand Old Party kicked off its national convention yesterday.

The addresses of the 35th Republican National Convention, which featured Reagan and defeated Republican challenger Patrick J. Buchanan, highlighted the foreign policy achievements of the Bush Administration and furiously attacked Democratic nominee Bill Clinton.

Earlier in the day Bush himself worked the Astrodome, talking to fellow Republicans and attempting to energize supporters. (Se story page 3.

Reagan called on the conventioneers to support his successor, describing President Bush as a "level-headed leader... with a steady hand on the tiller through the choppy eaters of the 90's, which is exactly what we need."

Reagan, aiming to help invigorate the lagging Bush campaign, allocated much of his speech to hard hitting assaults on the Democratic Party for its shortcomings--both in its presidential candidate and its congressional stronghold.

"A lot of liberal Democrats are saying it's time for a change, and they're right," said Reagan, as delegates waved "We Love Ron" signs and chanted his name. "The only trouble is they're pointing to the wrong end of Pennsylvania Avenue. What we should change is a Democratic-controlled Congress that wastes precious time on partisan matters of absolutely no relevance to the needs of average American...It's time to clean house."

Reagan criticized Bill Clinton for his claim that he will be the next ThomasJefferson, mocking his advanced years at the sametime. "Well, let me tell you. I knew ThomasJefferson. And governor, you are no ThomasJefferson," he said.

Former presidential candidate Patrick J.Buchanan also threw his support behind Bush lastnight in prime-time, stressing the importance ofBush's foreign policy record, in striking contrastto Clinton's.

"George Bush has been U.N. Ambassador, CIAdirector, envoy to China. As Vice President,George Bush presided over the liberation ofEastern Europe and the termination of the WarsawPact...Bill Clinton's foreign policy experience ispretty much confined to having had breakfast onceat the International House of Pancakes."

Describing the presidential race as a"religious war...for the soul of America," Buchananderided the Democrats as "radicals and liberals"who want change, "but not the kind of change wecan abide in a nation that we still call God'scountry."

While Buchanan forcefully encouraged supportersrally around the president, he did make it clearthat he still holds some reservations about Bush.

"I disagree with the President; and so wechallenged the President in the Republicanprimaries and fought the best we could...But I dobelieve, deep in my heart that the right place forus to be now--in this presidential campaign--isright beside George Bush."

Earlier in the day in the red-white-and-blueAstrodome, the conventioneers officially adoptedthe very conservative party platform, touted as"Mainstream Ronald Reagan." The process wasuneventful, and passed without much trouble.

On the protest grounds, abortion and AIDSrallies consumed much of the day, lining thestreets adjoining the Astrodome. Susan Payne, aHouston resident who took part in a pro-lifeevent, said there weren't any problems ordisruptions.

Payne, holding a sign that read "pro-life,pro-family," said there "is not a chance thatabortion will remain legal here because God isgoing to prevail." She said that abortionopponents "just haven't been loud enough yet."

Other protests were more violent. Gay rightsactivists clashed with police. Six people werearrested after 50 lay down in the street andanother burnt an effigy of Bush.

Rounding out the first-day schedule wereperformances by B.B. King and country-western starRandy Travis.AFP PhotoFormer presidential candidate PATRICK J.BUCHANAN