Liberals, Progressives, and Radicals

Here's a thought-provoking article that categorizes the left side of the U.S. electorate as liberals, progressives, and radicals:
Richard Kline: Progressively Losing.

Here's my slant on this:

• Liberals are socially liberal while fiscally conservative.
• Progressives see the need for continuous change to keep up with changing technology and its effects.
• Radicals are militants driven by extremely difficult personal or community circumstances.

These are all reasonable positions, although I happen to prefer the progressive to the liberal attitude.