DAVID RIVKIN & ELIZABETH PRICE FOLEY: Federal Antidrug Law Goes Up in Smoke: Irate about harmful spillover from Colorado’s marijuana legalization, two neighboring states sue to overturn it.

The attorneys general of Nebraska and Oklahoma have asked the Supreme Court to declare unconstitutional Colorado’s law legalizing marijuana. The lawsuit states that, “The Constitution and the federal anti-drug laws do not permit the development of a patchwork of state and local pro-drug policies and licensed-distribution schemes throughout the country which conflict with federal laws.”

Many conservatives have criticized Nebraska and Oklahoma for being “fair-weather federalists” because their claims hinge, in part, on Gonzales v. Raich, a 2005 Supreme Court decision, upholding the broad reach of Congress’s power to regulate commerce.

Conservatives’ ire instead should be directed at the Obama administration’s decision to suspend enforcement of the federal law prohibiting marijuana—a decision so warping the rule of law that the complaining states’ reliance on Raich is justified and necessary. . . .

States cannot be required to enforce federal law. But as the Supreme Court held in A rizona v. United States (2012), when the federal government doesn’t enforce its own laws, states still “may not pursue policies that undermine federal law.” Colorado’s decision to legalize and regulate the sale of marijuana undermines the Controlled Substances Act, giving a major boost to all segments of that business. Indeed, in an interview this month Colorado’s attorney general, John Suthers, acknowledged that his state is “becoming a major exporter of marijuana.”

Well, the Feds have largely given up on drug law.