“...such as the Westboro Baptists or Warren Jeffs’ polygamist Mormon cult...”
Neither of these are Christian. A Christian is someone who continues faith in Christ and his teachings, and terrorism is not a way of doing that.
Islam is a purely, self-serving religion that evades questions of fairness or right and wrong. It is a psychological disease for those who believe in it, and a curse for those who don’t believe in it.
Democrats, especially those who support the Obama cult, defend Islam because it works with their purpose of destroying Western Civilization.
To practice holy war, a Christian must ignore or rationalize away the plain teachings of his religion.
To NOT practice holy war, a Muslim must ignore or rationalize away the plain teachings of his religion.
Some in each group do exactly that, but this does not make such outliers typical of their co-religionists.