John Sununu apologized, not for the sentiment, but for these words: "I wish this president would learn how to be an American."

The former New Hampshire governor and White House chief of staff was speaking as a Mitt Romney surrogate, and the message was an old one, heard since Barack Obama was a presidential candidate. "This guy is not really one of us. He's someone and something else."

Got it. Heard it. Sure we'll hear it again. Birth certificates are no longer enough. From now on, one must pass the Sununu citizenship test.

Even for those who accept that President Obama was born in Hawaii, that state is, don't you know, unlike any other -- multiracial, multicultural and in the middle of the Pacific Ocean. Sununu, who was born in Havana, Cuba, has looked at the president's background and decided it doesn't fit, all irony apparently lost amid the bluster. Sununu's guy Romney, whose father was born in Mexico, mostly stood back looking sheepish. "Plausible deniability" is what it's usually called.

In another case of "are you now or have you ever been," a voice rising in defense of the latest accused American was Republican Sen. John McCain of Arizona, living up to his one-time maverick label.

He strongly defended Secretary of State Hillary Rodham Clinton aide Huma Abedin against unproven accusations that tie her to a supposed conspiracy of the Muslim Brotherhood to infiltrate the U.S. government.

McCain said on the Senate floor: "Huma represents what is best about America: the daughter of immigrants, who has risen to the highest levels of our government on the basis of her substantial personal merit and her abiding commitment to the American ideals that she embodies so fully."

While that should be the end of it, with Rep. Michele Bachmann, R-Minn., and other members of Congress floating the charges and asking for investigations, the issue is not likely to die. All it takes is murky guilt by association and a dose of hysteria.

I'm still trying to figure out these new rules. What do they mean? Some later additions to the United States -- we're talking Alaska, home of Sarah Palin -- are unquestionably American. Presumably, extreme weather, oil pipelines and the whole shooting-wolves-from-helicopters thing help it pass muster. While Hawaii, after all its years flying the American flag, remains a nice place to visit -- but you can't trust anybody who lives there.

And some children of immigrants -- Gov. Bobby Jindal, Republican of Louisiana, who is on Romney's vice presidential short list, and Gov. Nikki Haley, Republican of South Carolina -- are loyal Americans, while others are security risks. It helps if you're a conservative Republican governor.

What sounds silly at first, the blundering of clumsy political opportunists is starting to veer into frightening and familiar territory, a throwback to a part of life in the 1950s for which no one should harbor any nostalgia.

Americans aren't endorsing a return to the "Red Scare," when being a union or civil-rights activist could be enough to warrant an appearance before the House Committee on Un-American Activities. But plenty of people are shouting accusations of "communist," "socialist" and "fascist" from placards and rooftops. At the top of their list is the democratically elected president of the United States.

You would think Obama's achievements and the life he's made with his wife and children illustrate the fulfillment of the American dream -- a man without family name or fortune rising through hard work and education to the nation's highest office -- even if you disagree with his economic plan or health care law and want to vote him out in November.

But some opponents need to make him a man without a country, to use the ugly language of an ugly time, and to put his supporters in the same boat, preferably one headed away from U.S. shores.

This year, Rep. Allen West, R-Fla., echoed the language of Sen. Joe McCarthy when he said, "I believe there is about 78 to 81 members of the Democratic Party that are members of the Communist Party," and he didn't back down.

It's troubling when Sununu, Bachmann, West and so many others are only too willing to take on the un-American job of deciding who belongs in America, the first and only rule being: Agree with us on matters of politics and policy, or -- as West instructed liberals -- get out.

Where are all the voices of reason to pull them back -- to ask, as the Army's lawyer Joseph Welch once asked of McCarthy, "Have you no sense of decency?"

McCain has stepped up. Who's in line behind him?