Unions don't fix the economy. If American labor isn't competitive, the free market doesn't reward them with well-paying jobs and houses. For a brief postwar period, manufacturing subsidies made American unions powerful because they were large and highly-demanded. After that it's hard to really say unions won much of anything besides seniority perks.
I grew up near Detroit, I watched the UAW fall from grace firsthand. If I could snap my fingers and bring the jobs back, I would. But it's not what the economy wants. Fighting "the man" to bring them back eschews a simple economic truth.