Lost in the discussion of the Ferguson decision, immigration and the Islamic State is a national security issue of special importance to Utahns. It's an idea that Sen. Orrin Hatch helped kill long ago, in the middle of the largest nuclear arms buildup in history, and now it's back: the U.S. Air Force's emerging plan to build a mobile nuclear-armed missile.

Back in 1985, Hatch rightly questioned the cost, the need, the proximity to civilians and the environmental impact of mobile nuclear missiles. Thirty years later, the answer is the same: Don't do it.

The mobile missile plan was born out of politics, not national security. In the late 1970s, the Air Force began to worry that its long-range intercontinental ballistic missiles (ICBMs) would lose favor to the Navy's submarine-launched missiles. These concerns stemmed from the fact that stationary missiles are easier to find — and destroy — than submarines.

To keep up with the Navy, the Air Force developed a plan for a mobile missile system. The original proposal was for a network of 200 truck-launched missiles and 4,600 "hardened" shelters spread around Utah and Nevada. For each actual missile, there would be 22 decoys, imitating the weight, balance and electromagnetic properties of the real thing. The trucks would drive from shelter to shelter on a "racetrack" so that the Soviets couldn't target the real weapon. President Jimmy Carter approved the plan in 1980, with a price of about $95 billion in today's dollars.

Naturally, residents of Utah and Nevada objected to having their states turned into massive nuclear targets. A bipartisan, interfaith coalition emerged to kill the program including liberals in Congress, President Reagan's close confidant, Sen. Paul Laxalt (R-Nevada), and the Mormon church.

A 1981 statement from the First Presidency of The Church of Jesus Christ of Latter-day Saints reads, "Our fathers came to this western area to establish a base from which to carry the gospel of peace to the peoples of the earth. It is ironic, and a denial of the very essence of that gospel, that in this same general area there should be constructed a mammoth weapons system potentially capable of destroying much of civilization."

President Reagan ultimately killed the racetrack program, but the Air Force continued testing other mobile concepts. One variant was intended to operate on regular civilian roads, before the end of the Cold War relegated it to the history books.

Or so it seemed.

This September, Lt. Gen. James Kowalski, vice commander of U.S. Strategic Command, which oversees the military's nuclear forces, said that the Air Force favors a new system to replace the current Minuteman III nuclear-armed missiles, and hinted that it could eventually be based on a mobile platform. This is just as bad an idea today as it was in the '70s.

The Air Force's own recent study found that buying a new missile "will very likely cost almost two times — and perhaps even three times — more" than simply maintaining the current one. A new mobile missile could cost up to $200 billion, the study said, and would be hard to justify.

Meanwhile, the U.S. nuclear missile force continues a string of highly public embarrassments including cheating, drug abuse and security failures. The commander of the force was relieved last year after a drunken bender in Moscow ended with him telling nuclear secrets to "escorts" provided by Russian intelligence.

With federal budget cuts looming, it's clear that America cannot afford to rebuild its Cold War nuclear arsenal. Current plans for nuclear modernization could cost as much as $1 trillion. Frank Klotz, head of the National Nuclear Security Administration, told Reuters that, "The bill is coming due, and it's a huge bill." A bipartisan, independent report commissioned by the Defense Department recently called the plans "unaffordable" and a threat to "needed improvements in conventional forces."

Spending another $200 billion on a mobile missile would be a waste of taxpayer dollars. That money is badly needed for other defense priorities. And the idea of putting nuclear weapons anywhere near Utah's cities and towns is completely ludicrous. Let's hope Congress follows Hatch's example and lets the mobile missile stay in the history books.

Tom Z. Collina is policy director and Jacob Marx is a research assistant at Ploughshares Fund, a global security foundation.