It is nice to be 82 and still a working journalist. But Alistair Cooke, who is both, reports one problem when young reporters arrive to interview him:

"I am at the stage where I ask, `Does the name Adolf Hitler mean anything to you?"'Despite this gentle reminder that those who forget history are doomed to see it repeated on cable, Cooke has prevailed in broadcasting and will take due note of it early in the new year - on Jan. 13, to be precise.

He'll celebrate his 20th anniversary then as host of PBS' "Masterpiece Theatre," commencing a nine-week retrospective of some of its best dramatic bundles from Britain. But of course they include "Upstairs, Downstairs," "I, Claudius," and "The Jewel in the Crown."

If that's not enough, PBS will offer a Jan. 24 parody of the series, "Masterpiece Tonight," concocted by Gerard Alessandrini, whose "Forbidden Broadway" here regularly applies the needle to Broadway musicals.

A transplanted Englishman who gives urbane a good name, Cooke has been the only host of "Masterpiece Theatre" since it began on Jan. 10, 1971 with "The First Churchills" - one of his least-favorite shows, incidentally.

An elegant man, he favors blue blazers, gray slacks, and the graceful turn of phrase. Also jazz piano.

Born in Manchester, and a U.S. citizen since 1941, he first came here as a student in 1932. He returned as a man of print and broadcast who since 1938 has tried to explain America to the British, no mean feat.

In 1970, he embarked upon an even more difficult feat - explaining America to the Americans - in his acclaimed "America" series, a BBC co-production that NBC aired in prime time in 1972-73. It won four Emmies.

But it also almost prevented him from signing up for "Masterpiece Theatre." He was in Boston, filming the third "America" episode, when accosted by a young British producer, Christopher Sarson.

The "Masterpiece" idea - hosting a weekly series of British dramas adapted from famous novels - was explained. Cooke begged off, saying he'd be tied up on "America" for two years and constantly travelling.

But Sarson "was a deadpan scoundrel - and terrifically persuasive," he said.

As befits a man of his years and travels, he occasionally is asked to compare the America of, say, 1940, with the America of today. Given the chance to go cosmic, he instead offers a refreshing, unexpected answer.

"I couldn't do it," he says. "The standard thing is to talk about the loss of innocence. Every generation thinks it was innocent when it was young. It wasn't innocent. It was young."

He smiles when asked when, if ever, he'll sign off the air and retire.

"Oh, it may happen tomorrow. I live from day to day, and it's not for me to decide that. But I don't have any intention of doing that. I think when you retire, you keel over."