Explain how Americans came to associate union members with extremists.

The unions now have one thing in common. The majority of unions and the majority of members get their featherbedded fat deals courtesy of forcefully extorted taxpayers. Unions are dependent on the very central tenets of communism - confiscation of private wealth, and compulsory participation. Even in the public sector unions, there are ominous clouds on the horizon for the union thugs.