The U.S. Senate has some arcane procedural rules, and as ordinary Americans our eyes glaze over trying to decipher them. But it’s important for us to understand that Sen. Ted Cruz’s efforts to defund Obamacare are worthwhile and doable.

We shouldn’t preemptively surrender the fight to those who rammed through this outrageously burdensome and unaffordable ploy for government control of health care even though some are trying to convince us t...