To be clear, he doesn't lay all the blame at the feet of Republicans. The piece ends, "In short, partisan conservative media and its less influential imitators on the left are inviting their audiences to see the political world in black-and-white, conservative and liberal, good and bad, with the result that for the public and elected officials, it is harder to find common ground."
But, he does place much of the blame on the G.O.P, which he believes has gotten more focused and unbending attitude, and explains why with a discussion of history. In fact, Mr. Allen shows admiration for both sides of the aisle in how things used to work historically --
Dwight Eisenhower accepted the major legislation of the New Deal. John Kennedy started the legislative push for a substantial tax cut. Lyndon Johnson came from a Senate known for working across the aisle. Richard Nixon signed clean water and clean air legislation. Ronald Reagan raised taxes many times to deal with mounting deficits created by his 1981 tax cut; George H. W. Bush did the same, to resounding criticism from the Right. Bill Clinton antagonized elements of his Democratic base by supporting a balanced federal budget, free trade and welfare reform.
George W. Bush was different. His election in 2000 was, in hindsight, stage two of the Newt Gingrich revolution. Senator Lincoln Chafee (R.-R.I.) recalled, shortly after Bush’s election, that Dick Cheney quickly laid out to a small group of moderate Senate Republicans, “a shockingly divisive political agenda for the new Bush administration, glossing over nearly every pledge the Republican ticket had made to the American voter.” In his first term, President Bush abandoned international treaties, invaded Afghanistan and Iraq, and drove through two massive tax cuts that primarily benefitted [sic] wealthy Americans.
The full article is over on Salon.com