2014年经济学人 美国中期选举 沉寂的中间地带（在线收听）

America's mid-term elections

The silent centre

If moderates don't vote next week, extremists will thrive

ALL political campaigns involve a certain amount of looking voters straight in the eye and lying to them. But America's mid-term election campaign has involved more flim-flam than most. The Republicans, if you believe Democratic attack ads, oppose equal pay for women, want to ban contraception and just love it when big corporations ship American jobs overseas. The Democrats, according to Republicans, have stood idly by as Islamic State terrorists—possibly carrying Ebola—prepare to cross the southern border. And they, too, are delighted to see American jobs shipped overseas.

Only a blinkered partisan would believe any of these charges. Alas, partisans are far more likely than anyone else to vote, especially in elections like this one, where the presidency is not up for grabs.

A survey by the Pew Research Centre finds that 73% of “consistently conservative” Americans are likely to cast a ballot on November 4th, along with 58% of consistent liberals. Among those with “mixed” views, however, only 25% are likely to bother. That, in a nutshell, is why both parties are pandering to the extremes. Their strategy relies less on wooing swing voters than on firing up their own side to get out and vote. Often, this involves telling them scare stories about the other lot. The same Pew poll finds that dislike of the other party is one of the strongest incentives to vote. Republicans with a “very unfavourable” view of Democrats are far more likely to turn out, as are Democrats who loathe Republicans. With Barack Obama in the White House Republicans are angrier than Democrats, and that is one reason why they are expected to win. Most polls say they will capture the Senate and hold onto the House of Representatives.

America's cycle of polarisation and alienation is self-reinforcing. As the debate grows shriller, moderates tune out. Politicians come to rely more and more on the votes of die-hard partisans, so they say and do more extreme things, alienating yet more moderates. Most members of Congress are more frightened of being tossed out by their own party's primary voters—typically for the heresy of compromise—than they are of losing an election to the other party.

America's electoral system needs reform. It is too late to change the rules before this election, however, so it is up to moderates to walk to a polling booth and be counted. To those who grumble that there is no point voting because they don't like any of the candidates, we offer two counter-arguments.

Speak now, or be ignored

First, these elections matter. Control of the United States Congress—the body that writes the laws and holds the purse strings of the most important nation on Earth—is at stake. (So are 36 out of 50 state governorships and thousands of local offices—see article.) Individually, it may be rational not to vote: one ballot is unlikely to affect the outcome. But when whole groups stay at home—centrists, young people and non-whites spring to mind—their interests will be ignored.

Explore our map and guide to the 2014 mid-term senate races

Second, politicians are more sophisticated than they appear on the stump. Many are secretly embarrassed by the flame-grilled drivel they have to serve up to partisan audiences. Plenty hanker for the days when divided government meant that the centrists in both parties hammered out reforms together and ignored the frothing fringes. But all of them can count votes—very accurately, these days. And all tend to reward their supporters: to “dance with the ones that brung them”, as the saying goes. So if moderate Americans want to influence how their government taxes, spends, regulates and wages war, they should tick a box next week.