The selective nature of taboos in American political and media culture has been exposed this week. Democrats are free to impugn their opponents’ decency and patriotism while Republicans never are allowed to do so.

Speaking at a “private” dinner for Scott Walker (note: only Democrats are permitted to have truly private events), Rudy Giuliani violated one of the taboos of American politics with these words:

"I know this is a horrible thing to say, but I do not believe that the president loves America."

There is a norm in American politics to presume that all issues and disagreements are between people who are patriotic and love America, except for Republicans and conservatives. In other words, only Democrats must be presumed to be patriotic and full of love of country.  For example, Democrats are free to attack the Tea Party, which they have lumped together with terrorists. The Republican-controlled House was even called “terrorists” in White House offical communications. And when running for the presidency in 2008, Barack Obama labeled President Bush “unpatriotic” for his deficit spending.

But Democrats must be presumed to be decent, patriotic, and motivated purely by love of country. And when they are not, they cry foul, as did Debbie Wasserman Schultz, who called Giuliani’s words “ugly.” For the record, Rep. Wasserman Schultz a few months ago agreed that the GOP is worse than Ebola and the Islamic State. But apparently that is not ugly in her mind. There was no widespread media controversy over her words, as compared to Giuliani’s.

And even many conservatives reacted with shock at Giuliani’s frankness. For example, Megyn Kelly (via Mediaite):

“A lot of liberals don’t believe in American Exceptionalism,” Kelly shot back, “but that doesn’t mean they don’t love America.”

As Kevin Williamson points out, there is every reason to question Presient Obama’s love of country.

Does Barack Obama like America? The people around him certainly seem to have their reservations. Michelle Obama said — twice, at separate campaign events — that her husband’s ascending to the presidency meant that “for the first time in my adult lifetime, I’m really proud of my country.” She was in her mid 40s at the time, her “adult lifetime” having spanned decades during which she could not be “really proud” of her country. Barack Obama spent years in the Reverend Jeremiah Wright’s church as the churchman fulminated: “God Damn America!” The Reverend Wright’s infamous “God Damn America!” sermon charges the country with a litany of abuses: slavery, mistreatment of the Indians, “treating citizens as less than human,” etc. A less raving version of the same indictment can be found in the president’s own speeches and books. His social circle includes such figures as Bill Ayers and Bernadette Dohrn, who expressed their love of country by participating in a murderous terrorist campaign against it. Does Barack Obama love his country? Call me a rube for saying so, but it’s a fair question.

In fact, progressives as a whole have deep reservations about America:

For the progressive, there is very little to love about the United States. Washington, Jefferson, Madison? A bunch of rotten slaveholders, hypocrites, and cowards even when their hearts were in the right places. The Declaration of Independence? A manifesto for the propertied classes. The Constitution? An artifact of sexism and white supremacy. The sacrifices in the great wars of the 20th century? Feeding the poor and the disenfranchised into the meat-grinder of imperialism. The gifts of Carnegie, Rockefeller, Vanderbilt, Morgan, Astor? Blood money from self-aggrandizing robber barons.

The reason why the taboo against criticizing the love of country applies only to Democrats is because the question cuts too close to home for them, and they control the media enforcers of the taboo.