It would be difficult to concoct a Washington fantasy more delicious than this one: Barack Obama declares “war” on Fox News and Fox boss Roger Ailes counters by signaling that he will challenge the president in the 2012 election.

This is William Randolph Hearst, Citizen Kane stuff–great fodder for political junkies.

But Ailes is not going to be president, nor even the Republican nominee for president.

Ailes has taken himself out of the running — saying he “can’t take the pay cut” — but only after a day of wild speculation about his potential candidacy.

The speculation about Ailes was not entirely the stuff of parody. It was rooted in a measure of political and media reality. But only a small measure — sort of like the notion that former Bloomberg L.P. chief operating officer Mike Bloomberg as mayor of New York City?

Ailes does, in fact, know politics. He’s a veteran Republican political strategist who engineered Ronald Reagan’s 1984 “morning-in-America” reelection campaign and George H.W. Bush’s 1988 “kinder-gentler” win.

Ailes is, as well, the media whiz who helped get CNBC and a predecessor to MSNBC up and running before building the Fox News Channel (which he has served as chairman and CEO since 1996) into the conservative messaging center that it has become.

That got some political players and pundits talking about Ailes as presidential timber, according to the Washington-insider website The Politico.

“Friends and associates are encouraging Fox News chief Roger Ailes to jump into the political arena for real by running for president in 2012,” the site reported Friday.

Veteran pollster Frank Luntz, a mastermind of Newt Gingrich’s 1994 “Contract With America” campaign, was one of those talking up an Ailes candidacy. “I have known Roger Ailes for 29 years,” chirped Luntz. “No one knows how to win better than Roger.”

Perhaps, but “Roger’s” wins have been for others — Reagan, Bush Sr. and his current boss, Rupert Murdoch — not himself.

At 69 and with a look and style that says “Dick Cheney,” Ailes does not fit the image that even the most delusional Republicans say they’re looking for in a challenger to a young and vigorous Barack Obama.

Besides, Ailes is a behind-the-scenes man who, frankly, gets along better with Democrats — and even some liberals — than his fans or critics care to acknowledge.

Famously, Ailes tried to ease tensions with the White House earlier this month when he met privately with presidential adviser David Axelrod (and 2008 Obama campaign manager). As The Politico notes, “The meeting was not a success.”

The wrangling between the White House and the news network Ailes runs has turned into great theater — and a great boost for Fox. That fed the speculation about an Ailes run in 2012.

Ailes had enough of a sense of humor, and marketing, to let the talk swirl for a day.

But when the speculation and guessing was done, Roger Ailes let it be known that he would not be America’s Silvio Berlusconi. While Italian conservatives may have opted for an aging media mogul as their standard-bearer, American conservatives were never going to do so.

In fact, the character of the Republican Party is much more cautious than conservative parties in other countries. That’s why even Sarah Palin, the party’s immediate former vice presidential nominee and a media “star,” trails more traditional contenders in polls anticipating the race for the party’s 2012 nod.

Palin’s book, Going Rogue: An American Life, will undoubtedly outsell Mitt Romney’s upcoming tome, No Apology: The Case for American Greatness.

But books sales aside, the latest Rassmusen poll of likely GOP voters, tells us that only 18 percent favor former Alaska Governor Palin. Former Massachusetts Governor Romney is at 24 percent. But the leader is the more classically conservative Mike Huckabee, the former Arkansas governor whose easy style most closely mirrors that of party favorite Ronald Reagan.

And what of Reagan’s former campaign strategist?

Rassmusen did not include Roger Ailes’ name in the poll.

And the Fox CEO will thank him for that.

This “Ailes for President” boomlet entertained Washington insiders for a day. But it was never going to take the Republican Party — let alone the country — by storm.