A few years ago, I spoke to some political operatives in Germany who asked me why American campaigns were so negative. I almost laughed in their faces because, after all, these were the grandchildren of Nazis. But they were right. Since surrogates for John Adams and Thomas Jefferson played out their rivalry in newspapers, American politics has been incredibly negative, and the 2012 election will be the most negative campaign yet.

You want someone to blame? Don’t look at me or anyone else in the business of launching political attacks. And don’t blame partisanship or those Americans who feel so personally invested in our democracy that they pick a side. And don’t blame apathy, because really, who cares?

Blame the independent voter, that paragon of rationality who holds himself loftily above the partisan fray, unsullied by politics.

I hate independent voters. Independent voters will question your motivations for changing an old lady’s flat tire. Quick to believe the worst and slow to accept anything good, independent voters are the most cynical people in America.

You want a perfect example of the sourpuss cynic who is America’s independent voter? Picture a cranky, unfunny Kinky Friedman. In other words, Kinky Friedman. (Full disclosure: I managed Chris Bell’s gubernatorial campaign against Kinky in 2006 and consulted for Kinky’s 2010 bid for agriculture commissioner.)

Kinky’s campaign slogans (“How Hard Could It Be?” and “Why the Hell Not?”) exemplified the entrenched cynicism of the voters who, according to popular legend, decide close elections.

And they’re really not as pivotal as conventional wisdom would have you believe. In the past three close presidential elections, the candidate who lost the popular vote also won the independent vote: Gerald Ford in 1997, George W. Bush in 2000 and John Kerry in 2004.

“Independents are later deciders,” said Alan Secrest, a Democratic pollster. “Independents will be much more likely to be voting against the candidate they do not support than to be voting for the candidate they do ultimately support. Independents are more cynical, skeptical of campaign communications, and quicker to assume they are being taken advantage of by the government or powers that be.”

Secrest calls them the “What have you done for me in the last five minutes” voters. They are the ones who either forget or distrust whatever good a politician has done and wait till the last moment to make up their minds.

Independent voters are why campaigns are so negative. When aimed at partisan bases, political attacks can either get out your vote or demoralize the opposition, but Republicans and Democrats have already made up their minds. Campaigns launch attacks in October of an election year to get independent voters to quit dithering and make up their minds.

This summer’s fight over raising the debt ceiling showed how the cynicism of independent voters drives politicians to ratchet up the rhetoric.

It was clear to any independent observer that Republicans were sticking to their “cut the budget” guns and that the tea party wing of Congress was willing to default of the nation’s debt to curb spending. Meanwhile, the Democratic base skewered President Barack Obama for abandoning a hard line on taxes and for relentlessly seeking compromise.

An independent voter of electoral myth should have been able to see through the partisan poses and discern that Obama acted like an adult, trying to forge a compromise, while Republicans in Congress pretended they were in a summer stock stage adaptation “Lord of the Flies.”

A Gallup poll that came out in late July found that 72 percent of independents wanted a compromise solution to raise the debt ceiling “even if it is a plan you disagree with.” Both Republicans and Democrats favored compromise, but not as much.

Yet a CNN poll later found that three out of every four Americans thought both sides acted like “spoiled children” and that 62 percent of independents disapproved of the compromise on the debt ceiling.

Both Obama and House Speaker John Boehner compromised at great political peril to themselves, doing exactly what independent voters demanded they do. The grown-ups in the room averted a crisis, but the independent voters reacted like spoiled children. Boo hoo.

It is that mindset that allowed Republicans to play chicken with the debt ceiling and encourages — if not requires — campaigns to dial up negative campaigning in election years.