The market working is a great thing. The issue is when the market
doesn't work. There are many laws granting unions more power than they would otherwise have if the market worked.
For example, in some states, if 51% of the employees decide to form a union, the other 49% are forced to become members. Then the union can extract union dues from their paycheck, even if they don't want to.
Unions also destroy meritocracy, replacing raises based on merit with raises based on seniority.
Unions can increase wages far above what would happen if the market worked. At commercial airlines, you'll see some pilots making $200,000, and some making $30,000, for the same job, on the same route, with the same safety. Increasing wages above market prices causes unemployment, because the company is less likely to hire new employees. Without the union, in general you'll see lower wages, but also lower unemployment.
What'd I'd like to see is all laws mentioning the word union to be abolished. No laws protecting unions, and no laws preventing them either. If you can form a club, and raise your wages or working conditions, more power to you.