PRESIDENT OBAMA may be the most visible political casualty of the BP oil spill, but there is another big loser: the Tea Party. A mainstay of cable news programming for much of the last year, Tea Party coverage all but vanished during the month of May, according to the media-monitoriing service TVEyes, as the spill dominated the headlines. There are still people in funny hats shouting about bailouts and vowing to “take back the government.’’ But suddenly they’re a lot less prominent.

It’s seldom a good idea to think of cable news programming as a gauge of anything other than the decline of civic discourse. Yet it’s hard not to see a connection between the story that is captivating cable viewers and a shift in the national mood.

The Tea Party movement, animated by intense disapproval of government activism, has smacked up against an unprecedented environmental disaster that is providing a vivid daily illustration of why an activist government is sometimes necessary. There is little doubt about which force is prevailing. According to a CBS News poll, a majority of Americans now oppose offshore drilling, and nearly two-thirds say Obama should be doing more to stop the spill. This desire for more aggressive government action is the antithesis of the Tea Party ethos, and poses a problem for a movement that had been gaining steam.

The addled response to the disaster from the Tea Party’s icons hasn’t helped. Rand Paul, the GOP Senate nominee in Kentucky, implied that the spill was no big deal (“sometimes accidents happen’’) and called Obama “un-American’’ for taking a hard line against BP. Sarah Palin, who popularized the phrase “Drill, Baby, Drill,’’ claimed that Obama’s response had been too slow because he was in the pocket of the oil companies (harebrained even by her standards). Sharron Angle, who upset the establishment candidate on Tuesday to become Nevada’s GOP Senate nominee, wants to abolish the Environmental Protection Agency. No surprise, then, that a Washington Post/ABC News poll this week revealed that half of Americans hold an “unfavorable impression’’ of the Tea Party, up from 39 percent in March.

None of this mattered while Obama was floundering. The spill has diminished almost everybody, but him above all.

There’s some irony in this. A month ago his administration was adeptly handling three environmental crises at once: the tornadoes in Oklahoma, the floods in Nashville, and the early stage of the BP spill. “The response has been excellent,’’ Representative Jim Cooper of Tennessee said then. “I’ve seen more cabinet members in Nashville than I see in Washington.’’ Alabama’s Republican governor praised the administration’s performance in the Gulf.

Praise for Obama is far scarcer today. Politicians, like most Americans, have short memories. An administration that once boasted of its prowess is now fending off comparisons to its predecessor’s handling of Hurricane Katrina.

But that could be about to change. Last week, Obama belatedly seemed to grasp that the oil spill posed a real problem for him. He needed to do something about it, even if he couldn’t plug the leak. What he did was pick a fight over oil and attempt to draw a distinction between his own beliefs about the role of government and those of the Tea Party and its fellow travelers.

In a speech in Pittsburgh, Obama vowed to resuscitate a Senate energy-and-climate bill that was widely presumed dead. “The votes may not be there right now,’’ he said, “but I intend to find them in the coming months.’’ Recognizing a useful villain, he tipped his strategy of “rolling back billions of dollars of tax breaks to oil companies so we can prioritize investments in clean energy research and development.’’

This is a sleight of hand, but possibly a clever one. The White House is no closer to plugging the leak. Oil will continue to poison the Gulf. But if the locus of public debate is whether to deny oil companies tax breaks, and if voters come to associate government intervention in the marketplace with incentivizing clean technology rather than propping up General Motors, then Obama will find himself in a more advantageous position. And the Tea Party may well be in the news again — just not in a way that it likes.

Joshua Green is senior editor at The Atlantic. His column appears regularly in the Globe.

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