Richard Cheney spoke to Republican Congressmen at the Capitol Hill Club the other day, giving them a sort of pep talk on the importance of maintaining a Cheneyite view of the world and not letting the guy in the White House be seen as taking the lead in confronting ISIS, the feared terrorist group of the moment. Mr. Cheney's remarks were not publicly reported but according to one of the Congressmen in attendance the former vice president “basically said that President Obama has actually done things that have supported the Muslim Brotherhood. But on the other hand the Muslim Brotherhood is really the beginnings of all the Islamist groups that we’re now dealing with; Hamas, ISIS – all of those groups.”

Leave aside for now the absence of any reason for anyone to listen to advice on such matters from one of the chief promoters of the war of choice that directly spawned ISIS. Leave aside also whether the description of the Obama administration's posture toward the Muslim Brotherhood resembles its actual policy. The administration has done little more than wrist-slapping in response to the Egyptian military regime's overthrow of a democratically elected Muslim Brotherhood president and its subsequent brutal suppression of the group.

Focus instead on the lumping together into one undifferentiated stew of “all the Islamist groups.” Sadly, that primitive way of categorizing political actors in the Middle East is not limited to Mr. Cheney. Former presidential candidate Mitt Romney did much the same thing. Partly this practice reflects the usual politically motivated games of association. When something as fearsome and salient as ISIS appears on the scene, expect that game to be played. Thus Israeli prime minister Benjamin Netanyahu, in his government's efforts to justify the recent turkey shoot in the Gaza Strip, has been fervently trying to equate Hamas with ISIS. Similarly, those endlessly waving the bloody shirt of Benghazi are making sure we hear Benghazi and ISIS in the same sentence. But there is ignorance, and probably prejudice, that runs more deeply than such political tactics.

Political Islam is not an ideology. It is more a sort of vocabulary that has been adopted by a very wide range of groups, parties, and movements, ranging from the most moderate and democratic to the most violent and extreme. It is a vocabulary that embraces a very large part of the political discourse in the Middle East, a fact that reflects the belief of adherents to one of the world's major monotheistic religions that their religion provides meaning and guidance for most human affairs, public as well as private. That vocabulary will not go away, and there will always be a plethora of diverse groups that define themselves in terms of that vocabulary.

Failure to understand all that means a failure to understand much of what is going on in the Muslim world and especially in the Middle East, from politics in Egypt to internal conflict in Iraq. With ISIS rearing its ugly head, one particular consequence of this failure deserves to be highlighted: bashing and rejecting “all the Islamist groups”no matter how peaceful and moderate—and lumping them indiscriminately with the most horrid and extreme groups—aids the cause of the violent and extreme groups. Without accepted peaceful channels for anyone with a grievance and an Islamic bent to pursue his objectives, the violent channels appear more attractive. The bashing and rejection also lend credence directly to the extremists' message that violence is the only way in which Islamic values will ever be incorporated into public life.

Egypt is an ongoing demonstration of this reality. The Egyptian Muslim Brotherhood was for many years remarkable in its forbearance in the face of being legally banned, rejecting the violent methods of radical Islamist groups such as the Egyptian Islamic Jihad and al-Gama'at al-Islamiyya. When it was finally given the chance to compete fully and openly, as well as peacefully, for political power, it did so. Now the al-Sisi regime's bludgeoning of the group has stimulated an upsurge in terrorist violence in Egypt, and most recently inroads in the country by ISIS.

The ISIS leadership no doubt welcomes the indiscriminate lumping of itself with everything Islamist, with the likes of the Muslim Brotherhood being taken down in the process, as the al-Sisi regime is doing in Egypt and as Mr. Cheney was doing on Capitol Hill. The lumping reduces the competition ISIS would otherwise be getting from more moderate groups appealing to an Islamist clientele which would have good reason to be appalled by the methods of ISIS. The lumping also helps ISIS to pose as the energetic champion of all Muslims against the depredations of a supposedly anti-Muslim United States.

Crude, primitive rejection of everything Islamist has many unfortunate effects. Helping ISIS is one of the effects we ought to worry about at the moment.