So then why did Mahler emerge in such an overwhelming way after 1960? The persuasive Bernstein started pushing the Mahler symphonies hard at a New York Philharmonic centennial festival that year, identifying completely with the composer as an agonized figure racked with dual identity issues.

Technology made it possible to get a Mahler symphony onto one or two LPs -- before that, you needed a forklift to carry a stack of 78 rpm discs -- and stereo really brought out the details of his stupendous orchestrations. Technical standards were rising, orchestras were better able to negotiate these demanding works; even youth orchestras could play them passably, or much more so.

But it was also the tumultuous times -- of sky-high hopes dashed by apocalyptic tragedies, of the status quo being challenged -- that made Mahler's message resonate. Imagine listening to the Sixth and Ninth symphonies for the first time in 1968 with the assassinations, the Chicago convention, Prague and Vietnam in the background -- as I did as a kid.

In his famous 1967 essay "Mahler: His Time Has Come," Bernstein follows a long list of the cataclysms of the 20th century with this comment: "Only after all of this can we finally listen to Mahler's music and understand that it foretold all."

This music was more than a soundtrack to the events; they amplified each other to a terrifying roar.

A few years later, Mahler's music did become a soundtrack -- to Luchino Visconti's "Death in Venice" -- whose lead character was based, with extreme license, on Mahler himself. The mixture of Mahler and humid, cholera-ridden Venice created a haunting image, further fueling the Mahler boom.

And the boom continues. What Bloch noticed a century ago could apply to the reactions of today's audiences, who never heard the warnings to stay away.

Yet Tilson Thomas isn't so sure that the boom is permanent. "Even at this stage, [some] people in Europe are still uncomfortable with his music. Still," he said.

"He's satirizing them, not treating them respectfully, too many quirks. It is exactly those quirks that make him appealing to [Americans]. The whole picture of man's activities is there, and that big picture is disturbing to some people."

For now, Mahler is much in demand; even the Vietnam National Symphony is planning a massive-scaled performance of the Eighth in October. The L.A. Philharmonic has several Mahlers on the calendar.

Don't expect another picket line this time. Mahler doesn't need one anymore.

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