Adventist historian Milton Hook describes it as "Adventist fundamentalism." He cites the aggressive preaching style of George Burnside who attacked Roman Catholics and "apostate" Protestants. Hook says this turned many away, and some of the remaining merely "loved a religious dogfight," and converts "often generated dust storms of intolerance and became clones of militant dogmatism among their peers." He states this style of evangelism was once the norm among Adventist preachers, and had roots in 19th century Methodism in the United States.