In an earlier column, I briefly addressed the similarities between the utopian ideology of the Islamic State and that of the global communist movement. I have also compared the counterinsurgency efforts used against the two movements in the past. But as I was writing about the structure of the Islamic State last week, I encountered more and more parallels to the global Marxist movement. This got me thinking even more intently about the similar ways that the two -- despite their differences -- have applied, encouraged and supported the use of violence. In light of these parallels, the lessons derived from the decades-long struggle against communism throughout the world may provide important guidance for the continuing fight against jihadism....