Why do older people who remember segregation and pollution protests feel compelled to stand against current political trends?

Every time I see the French take to the streets, the government actually responds. In the U.S., protests just make headlines for a week and then disappear. What makes the French model of protest still work?
Do you think the pressure from Democrats on the issue of health care can be seen as a vulnerability for Republicans ahead of next year's midterms, as some in the GOP have suggested?