Does the U.S. spend too much on defense? Many believe that’s the case. They note that, in constant dollars, the Pentagon’s budget is now higher than it has been. And, they argue, much of that money is wasted through mismanagement and excessive overhead costs.

They also like to compare U.S. defense spending with that of the next 10 or 12 top-spending countries, claiming that this shows the U.S. is wildly overspending. They further argue that “de-militarizing” U.S. foreign policy—relying more on diplomacy and economic measures and less on global policing and “adventurism”—would allow for much smaller defense budgets without any loss of security.

But much, if not all, of this criticism, is deeply flawed. For example, the "U.S. v the next 10 countries" spending comparison assumes that our competitors are open and honest about what they're spending. They aren't. It also ignores the fact that defense dollars go much further into our adversaries' economies. (For starters, just think about the pay scales in China and North Korea.)

But, they complain, many of those 10 countries are U.S. allies. If they can spend so little, surely the U.S. can spend less too. Again, this assumes that our allies’ investment levels in defense are all reasonable.  And, again, they aren’t. Many of our allies in NATO and elsewhere are dramatically under-spending on defense, falling well shy of their commitments. Until they live up to their commitments, the U.S. has no choice but to compensate for their military weakness.

>>> Budget Delay Is the Enemy of Defense

But the biggest problem with the cut-the-budget arguments is that they ignore the fundamental fact that defense spending should be determined by how much is needed to produce the type and amount of military power needed to deter or prevail in war. Today’s defense budget must not be held hostage to what was spent in the past, without regard to how conditions have changed.

Even if defense spending kept pace with general inflation, the military would still decline in effectiveness because advances in technology outpace the value of money. More capable sensors are better able to find things; modern weapons are more effective at destroying things; the ability to share better information about the battlespace makes military action more complex and lethal.

Our rivals’ platforms, weapons, and forces are continuously improving on all these fronts, and ours must, too. This is why a ship or plane needed to win in battle today costs three times as much in constant dollars as its 1970s predecessor, a tank five times as much, and the equipment to outfit a soldier 16 times the rate of inflation. Conflict—even preparing for it—is competitive. Decide to stop competing, and what you have really decided is to lose.

A decision to stop modernizing the military would save a lot of money, but it would also leave the U.S. with a rapidly obsolescing force unable to defend national interests, render aid to treaty allies, or stand against naked aggression. We've done this before, and it does not end well.

After the Cold War, NATO effectively disarmed, convinced that peace would reign supreme. Unfortunately, China and its thuggish colleagues had other ideas and started investing in new capabilities at an astonishing rate. In the last 30 years, China has become a first-rate power in space, cyberspace, artificial intelligence, unmanned systems, and advanced weaponry.

North Korea became a nuclear power. Iran started its own nuclear program, developed the largest inventory of ballistic missiles in its region, and redoubled its support to surrogates attacking Israel, Saudi Arabia, and others.

Russia eventually regained its footing and reasserted itself—invading Georgia and Ukraine, propping up Bashar al-Assad in Syria, and generally bullying the Baltic and Nordic countries, all while trying to create fissures within the NATO alliance and waging cyberwar on everyone else of consequence.

Should the U.S. defense budget not account for this? Has modern military power in the hands of expansionist, authoritarian regimes ceased to be a concern? Has the world shrunk in size such that smaller U.S. forces, primarily based at home and possessing old equipment, can easily get to where they are needed and prevail against more numerous enemy forces equipped with modern capabilities?

Perhaps it is useful to think…just for a moment…about what the world might look like if defense reductionists had their way. We can see the impact their European cousins have had among NATO partners: militaries with minimal ability to project and sustain power beyond their borders and scant ability even to protect themselves.

No wonder Xi, Putin, Khamenei, Jong-Un, and Assad seem more emboldened than deterred these days.

>>> The Administration’s FY 2022 Defense Budget Outline

It really is not a choice between tax dollars for defense or for the host of new social programs sought by the Left. Nor is it about valuing military power more than diplomacy. It is about what history and human nature tell us about strength and weakness, focus and distraction, courage and cowardice, and the necessity of facing harsh realities rather than seeking comfort in pleasant fictions.

We need to get serious about what it takes to keep America safe and its interests protected in the real world of today, not in imaginary worlds where competitors hold their ambitions in check, field armies with obsolete gear, and our allies are perfectly able to do most of the fighting on our behalf.

Risk is measured in what you are willing to lose and what you are willing to invest in protecting the things you value most. The U.S. defense budget is where this discussion must take place. It is no place for reality to be replaced by make-believe.