To see why unions are going extinct, check out the SEIU’s latest alert. Union president Mary Kay Henry warns that “collective bargaining rights are under attack — again.” The threat comes from a bill . . . that would let employers pay higher wages. Yes, the union considers higher pay “a federal attack on your rights at work.” Currently, union rates are both minimum and maximum wages. Unionized businesses may not pay any more or less without the union’s permission. Senator Rubio’s RAISE Act turns union rates into minimum wages only: Employers could always pay more.

They often want to. Individual performance-pay can motivate employees to work harder. This increases both wages and profits. Unfortunately, most unions dislike performance pay. As Henry put it, unions want to “negotiate contracts that create a uniform, fair process for granting wage increases.” So everyone gets the same amount — no matter how hard they work.

The RAISE Act allows employers to reward individual achievement with higher pay. The SEIU considers this intolerable, and thinks “it undermines the fairness collective bargaining contracts bring to the workplace.” Worse, “employers would be allowed to ignore what they agreed to in collective bargaining agreements — and that’s not fair.” No wonder so few workers want to unionize.

— James Sherk is senior policy analyst in labor economics at the Heritage Foundation.