Sen. Joseph Lieberman, the 2000 Democratic nominee for vice president, has endorsed Republican Sen. John McCain for president. It’s a coup for McCain, struggling to reignite his once frontrunning campaign. And looking over the rest of the field, libertarian voters might even conclude that McCain has a pretty good record on a lot of economic issues.

But the Lieberman endorsement will remind those libertarian voters of all the positions that pushed them away from McCain in the first place. Lieberman and McCain are perhaps the two leading supporters of the Iraq war in the Senate. They are coauthors of a bill to impose costly new regulations to fight global warming. They both support restrictions on political speech.

As I’ve noted before, some Republicans think no issue matters except doubling down on the floundering war effort, so they consider Lieberman an ally, even a man who should be a heartbeat from the Oval Office in the next Republican administration. But you have to ignore Lieberman’s entire career to see him as an ally of conservatives.

As Robert Novak pointed out back when Republicans were endorsing Lieberman for reelection,

Lieberman followed the liberal line in opposing oil drilling in ANWR, Bush tax cuts, overtime pay reform, the energy bill, and bans on partial-birth abortion and same-sex marriage. Similarly, he voted in support of Roe vs. Wade and for banning assault weapons and bunker buster bombs. His only two pro-Bush votes were to fund the Iraq war and support missile defense (duplicating Sen. Hillary Clinton’s course on both).

Lieberman’s most recent ratings by the American Conservative Union were 7 percent in 2003, zero in 2004 and 8 percent in 2005.

I actually agree with him on a couple of those votes, though I wouldn’t expect that conservatives would. The National Taxpayers Union said that he voted with taxpayers 9 percent of the time in 2005, worse than Chris Dodd or Barbara Boxer. Maybe because of all the Republican love in 2006, he soared to a 15 percent rating.

In a previous speech, Lieberman called for a tax increase so that we could continue the war without “squeezing important domestic programs, as we have been doing”–his view of a period during which federal spending rose by one trillion dollars:

During the Second World War, our government raised taxes and we spent as much as 30 percent of our Gross Domestic Product to defeat fascism and Nazism. During the war in Korea, we raised taxes and spent fourteen percent of GDP on our military…Today, in the midst of a war against a brutal enemy in a dangerous world, we have cut taxes and are spending less than five percent of GDP to support our military…It is not an acceptable answer to push the sacrifice of this war against terrorism onto our children and grandchildren through deficit spending, as we have been doing. And it is not an acceptable answer to pay the costs of this war by squeezing important domestic programs, as we have been doing.

Lieberman may help McCain with Republican hawks, but he’s not likely to help with New Hampshire’s growing contingent of disaffected libertarian, centrist, and independent voters, the ones who swung the state firmly into the blue zone last fall.