Political Extremism and Radicalism This link opens in a new windowSearch primary sources on peripheral groups deemed "extreme" or "radical" by contemporaries on both the right and the left from the early 1900s to the present. Find sources on anti-Catholic, anti-Semitic, anti-war, communist or socialist, creationist, environmentalist, hate, holocaust denial, new left, survivalist, and white supremacist/nationalist groups. Most materials come from the US and Great Britain, but a few are from Australia and other countries in Europe. (Gale)