The Humvee looked like a steel monster when it first arrived on Army bases in 1985. The Jeep, the venerable all-purpose vehicle that carried soldiers, supplies, and armaments in World War II and through the next four decades, looked downright cute alongside its replacement.

Back in the 1980s, the Department of Defense’s top brass reasoned that America would be facing new foes in never-before-imagined military engagements in the new century. The Humvee was designed during the height of the Cold War for the fierce battlefields of the future.

Yet two decades later, the Humvee is going the way of the Jeep. In fact, it will have served the American military not even half the amount of time that the rugged little Jeep did.

The Humvee, which was once the favorite weekend drive of tough-guy actors like Arnold Schwarzenegger and Sylvester Stallone, now has attained the status of a quaint, Cold War relic. Mind you, this was a multi-purpose vehicle that could carry payloads of 5,300 pounds and be dropped from an aircraft.

It seems that those who envisioned a do-anything, go-anywhere military vehicle in the 1980s couldn’t have imagined just how brutal and unpredictable warfare would become two decades hence.

So the Department of Defense is quickly replacing the Humvee with a new all-purpose monster: the MaxxPro Mine Resistant Ambush Protected, or MRAP, vehicle built by military-equipment manufacturer Navistar Defense, LLC.

Its recent arrival at key bases in the Middle East marks new efforts by the Department of Defense to address the most common danger facing American troops in the Afghan and Iraqi theaters: casualties and injuries from so-called Improvised Explosive Devices. IEDs are so potent that not even Humvees can withstand them.

An Army spokesman, Captain Charles Jaquillard, tells us that the undercarriage of the MaxxPro is heavily armored and its hull is shaped in such a way so as to deflect as much energy from enemy mine blasts as possible. Citing security concerns, he would not reveal the thickness of the glass used on the windshield or the materials used to armor its body panels. At a recent viewing of the truck, we weren’t allowed to hop inside.

The Department of Defense heralds the MaxxPro as its no. 1 procurement priority. The Marine Corps already has ordered 743 MaxxPro vehicles that costs about $410 million. Navistar International Corp., which owns Navistar Defense, LLC, reports it has so far delivered 2,000 MaxxPro transports to the military.

Although the government doesn’t buy MaxxPros at dealerships, each 40,000-pound vehicle would have a sticker price of roughly a half-million dollars.

On Tuesday, one of the defense industry’s largest trade groups, the Aerospace Industries Association, released a report to Congress that called for a procurement budget of up to $150 billion for the Pentagon in 2009. It’s a sum that’s significantly higher than the Bush administration’s current request of $104 billion.

This trade group’s point is that those who procure and equip the troops know more about their needs than anyone else. It’s a philosophy that has helped bring democracy to Iraq and justice to Afghan terrorists. It’s why America hasn’t suffered another terrorist attack on native soil since September 11, 2001.

We can assume that this $150 billion — about 4% of GDP — is a figure that’s also higher than what Barack Obama would have in mind if he were to become commander-in-chief next year.

Some 500 of these behemoths are rolling off the assembly lines each month. That’s more than an ounce of prevention, but the long-term cost of skimping on the right kind of defense procurement is astronomical.

Mr. Akasie is a contributor of The New York Sun.