This is a trap into which some candidates will fall. But the Iranian nuclear program, the Islamic State, the People’s Republic of China and Vladimir Putin must all be greater priorities for the next president than control of the southern border — even though that control is also an element of the nation’s security.

The Republican Party has been cautious about which journalists will be asking questions in debates and framing the issues of the GOP primary. But the anti-illegal immigration absolutists, who brand every immigration reform proposal as “amnesty,” distort that primary as surely as a debate panel of Media Matters propagandists ever could. There is no upside in generalizing about all immigrants (even all illegal ones) from this murder, or from the legion of “sanctuary cities.” And there is considerable political downside to it as well.

There is also the question of consistency. If states may now simply go their own way on dope laws, why shouldn’t cities legislate their own immigration policies? After all, both are flouting specific federal laws and the Supremacy Clause of the Constitution. To run a “rule of law” campaign will oblige every candidate to consistently demand that rule in every case. If a candidate finds an applause line for a condemnation of sanctuary cities, they should be willing to then condemn marijuana sanctuaries as well, or at least explain why the two categories of law-breakers are different.