High Democrats be-labor Reagan

Democratic leaders have taken over where AFL-CIO president Lane Kirkland left off in a coordinated campaign to weaken Ronald Reagan's support among workers and the public, and to create a strong opposition movement.

Former Vice-President Walter F. Mondale and House Speaker Thomas P. O'Neill Jr. drew warm welcomes from the union's centennial convention and responded by condemning, in Mr. O'Neill's words, ''the notion that the answer to the country's economic problems is to throw millions of people out of work.''

Mr. Mondale first fanned anti-Reagan fires by charging that ''the whole country is imperiled by this administration. They have put in place a radical economic program and it has failed. They offered us a painless panacea, and it only increased our pain.''

O'Neill continued to stress a recurring convention theme - a charge that the administration is allowing unemployment to climb toward 9 percent, when as many as 10 million would be jobless, in a ''heartless'' fight on inflation. Reaganomics, he said, is ''a house of cards about to collapse.'' The President's confidence in a balanced budget ''is now buried in red ink.'' And his tax program, O'Neill said, is one designed ''for big business and the wealthy - taking money away from the poor and the middle class and giving it to the rich.''

The House Speaker left no doubts about the purpose of the Democrats' convention campaign: The party needs labor and labor needs the party. ''It's great to be back together again . . . we who made America,'' he told delegates.

Sen. Edward M. Kennedy, a big favorite of the unions, will address the convention today (Nov. 18).