When I ran for a seat in the U.S. Senate in 2006, I thought the mudslinging and negative campaigning had reached epic proportions, and couldn’t get much worse. Boy was I naïve.

Judging from today’s campaign commercials, you’d think the candidates were a pack of degenerates, bigots, crooks and incompetents -- and those are the good ones! We’ve sunk as low as calling candidates "whores" and "witches."

Poll after poll shows Americans are sick to death of character assassination campaigning. But candidates still do it, with increasing frequency and viciousness. Why? Because negative campaigning works.

Not because it convinces us to switch our vote from one candidate to the other, but because it convinces us not to vote at all.

That’s the dirty little secret of modern campaigns – it’s all about turnout – if you can’t get people to vote for you, at least you can stop them from voting for the other guy. If you can get more of your opponents’ supporters to stay home on election day, than he does of yours, then you win.

But is this any way to run a democracy?

Every year fewer of us vote. Good candidates don’t want to stand for office, for fear the snarling pack of dogs will tear apart their families and their good names. We elect leaders that few of us like, or agree with, or admire. We have to hold our noses when we pull the voting lever.

And what’s the result? Endless campaigns, because candidates need to raise a lot of money to buy TV time to trash their opponents. And worst of all, we’re destroying our faith in our system of government and our elected officials. We’re starting to hate them all – throw the bums out is the most popular slogan of our times.

So how to do away with the negative campaigning that is a cancer to our system? We can’t make it illegal without infringing on free speech. But we can undercut its effectiveness.

What if everybody had to vote on election day, or pay a fine if they didn’t? Candidates wouldn’t bother with negative campaigning, because it wouldn’t work.

It feels un-American, somehow, to force people to vote. We don’t like compulsory anything, much less compulsory voting. But there is nothing un-American about paying a fine. You can stay away on Election Day -- but you have to pay.

That’s what they do in Australia, Chile and Singapore, where voters get fined for not voting. The price is less than they'd pay for a a parking ticket, but it gets some 90% of their people to the polls, as opposed to less than 20% in our own primary or off year elections. And if they don’t like any of the candidates, they can leave their ballots blank.

And, guess what? In those countries the very best people run for office, there is very little negative campaigning, and their election season is mercifully short.

Kathleen Troia "K.T." McFarland is a Fox News National Security Analyst and host of FoxNews.com's "DefCon 3." She held national security posts in the Nixon, Ford and Reagan administrations. Be sure to watch "K.T." every Monday at 10 a.m. ET on "DefCon3" -- already one of the Web's most watched national security programs.

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Kathleen Troia "K.T." McFarland is a Fox News National Security Analyst and host of FoxNews.com's "DefCon 3." She served in national security posts in the Nixon, Ford and Reagan administrations