Robert Lighthizer has written an op-ed in the New York Times arguing that McCain's free trade rhetoric isn't really Republican, because past Republican presidents have been protectionists:
The first significant Republican free trader was President Dwight Eisenhower. But Harry Truman tried to recruit him to run for the White House as a Democrat, and his political affiliation was not clear until he actually began running for the 1952 Republican nomination. Conservatives in 1952 supported the presidential bid of Robert Taft, a steadfast opponent of free trade.
If you watched the Republican presidential debates — and had no other knowledge of economic history — you might believe that Ronald Reagan, the personification of modern conservatism, was a pure free trader. During a debate in Michigan, for example, Mr. McCain said that President Reagan “must be spinning in his grave” to hear Republicans expressing concerns about free trade. But while free traders like to quote some of President Reagan’s open-markets rhetoric, they did not like many of his actual trade policies.
President Reagan often broke with free-trade dogma. He arranged for voluntary restraint agreements to limit imports of automobiles and steel (an industry whose interests, by the way, I have represented). He provided temporary import relief for Harley-Davidson. He limited imports of sugar and textiles. His administration pushed for the “Plaza accord” of 1985, an agreement that made Japanese imports more expensive by raising the value of the yen.
This is as ridiculous as the attempts to slander the Democratic party by noting that it was the party that opposed reconstruction. Yes, Republicans used to be the party of the industrial north, and as such, in favor of high tariffs--but that ended fifty years ago. And noting that Republicans occasionally cave to protectionist pressure is not the same thing as saying that they're against freer trade.
While there are free traders in each party, and protectionists in both, on net the Democrats are now the more protectionist party, because a huge portion of their base is the unions and the Rust Belt. George Bush has not been perfect on trade, but he's been actually quite good within the limits imposed by popular sentiment and political need--yes, steel tariffs and all. His father was the one who did most of the heavy lifting on the transformation of GATT into the WTO. McCain is not substantially breaking with that legacy.
Update Egregious misspelling of Mr Lighthizer's name corrected; that's what I get for blogging before my morning coffee. Meanwhile, Daniel Drezner has more.