Rep. Allen West, a Florida Republican, was recently captured on video asserting that there are “78 to 81” Democrats in Congress who are members of the Communist Party. Of course, it’s not unusual for some renegade lawmaker from either side of the aisle to say something outrageous. What made West’s comment — right out of the McCarthyite playbook of the 1950s — so striking was the almost complete lack of condemnation from Republican congressional leaders or other major party figures, including the remaining presidential candidates.

It’s not that the GOP leadership agrees with West; it is that such extreme remarks and views are now taken for granted.

We have been studying Washington politics and Congress for more than 40 years, and never have we seen them this dysfunctional. In our past writings, we have criticized both parties when we believed it was warranted. Today, however, we have no choice but to acknowledge that the core of the problem lies with the Republican Party.

The GOP has become an insurgent outlier in American politics. It is ideologically extreme; scornful of compromise; unmoved by conventional understanding of facts, evidence and science; and dismissive of the legitimacy of its political opposition.