In the rancid politics of the moment, no candidate enjoys public favor for any length of time, a month, say, or even a week.

Mitt Romney has, for sure, had his misery moments, most of them self-inflicted. And those woeful wannabes who opposed him in the Republican primaries, losers such as Newt Gingrich, Rick Perry, Michele Bachmann, et al., have had an even worse time. President Obama has fared no better, having just gone through what the experts proclaimed as a three-month slump.

Even when a candidate seems set for a run of upbeat events and a batch of favorable press clippings, things can go amiss.

Take Romney's international adventures last week. The program called for him to take a pre-election victory lap in Europe and Israel to burnish his foreign policy credentials, or at least to acquire some, while a beleaguered Obama battled a stubbornly sluggish economy and a sullen Republican House of Representatives. But it didn't turn out that way at all.

Romney, as even Republicans acknowledged, blew it, questioning Britain’s Olympic preparedness and attributing Palestinian failure to cultural inferiority. Meanwhile, Obama, without lifting a finger, had an unexpected turn of good fortune.

Romney was in Jerusalem last weekend parading his Jewish-American supporters, kissing Benjamin Netanyahu’s hand and promising to be a less critical friend of Israel than Obama has been, but Israeli Defense Minister Ehud Barak somehow didn’t get with the program. Barak was effusive in his praise for Obama.

“I should tell you honestly,” Barak told an interviewer, “that this administration under President Obama is doing, in regard to our security, more than anything I can remember in the past.”

Similar expressions of support for Obama came from Shimon Peres, the Israeli president, who said Israelis’ security needs were “never better met than today under President Obama. This is a fact.”

These two, Barak and Peres, really know how to hurt a guy. Their timing, from Romney’s point of view, was dreadful. Sometimes, it seems Mitt, even with all his money, can’t buy a break.

As if that wasn’t bad enough, along comes Adm. William McRaven, U.S. special operations commander and boss of the SEALS team that took down Osama bin Laden. McRaven, the most celebrated military figure of the moment, had words of high praise for Obama during a rare interview with CNN’s Wolf Blitzer.

“What kind of commander in chief is he?” Blitzer asked.

“The president of the United States is fantastic,” McRaven replied.

Emphasizing that he is “not a political guy” and that he worked well with President George W. Bush, too, McRaven went on to say this about Obama: “This is about a commander in chief who I’ve had the opportunity to engage with on a routine basis, and watching him and the decisions he makes along with his national security team. They’re a very impressive group of guys and gals.”

Until now, McRaven has keep an exceedingly low profile in keeping with his job. The work of special ops, after all, is done primarily in the dark. So the timing of his rare public interview raises questions: Why now in the heat of a nasty president campaign?

It’s just guesswork, but it could be designed to counter the emergence of another swift boat-style operation designed to damage another Democratic presidential candidate, as the original swift boaters damaged Sen. John Kerry in 2004.

This one, styling itself “Special Operations Speaks,” put out a fuming-at-the-mouth statement by one Larry Bailey, a retired SEAL captain. “If you and I don’t get this man out of office,” the statement read, “he’s going to destroy our military, undermine every ally we have and arm our enemies to the teeth.”

Bailey, if he actually wrote that, sounds like the sort of overheated guy who should be writing horror scripts for grade-B movies.

So what we have here is a week that was supposed to be a kind of coronation for Mitt Romney, but instead produced unexpected kudos for Barack Obama. It’s been like that all year. Neither candidate is up or down for long and nothing is really predictable.

Well, that’s not quite true. Congress has been down all year and getting lower in public esteem by the day. It’s not likely to get any better. It’ll probably get worse. And that is predictable.

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