Everyone agrees that President Donald Trump’s proposed massive missile defense system – nicknamed the “Golden Dome” – will carry huge costs. The question for policymakers is whether the system serves as a necessary safeguard for America, or a destabilizing force in the world’s complex global nuclear arms balance.
It’s a question that hinges on whether any current defense strategy can effectively counter the fast-emerging class of modern weaponry.
Both Republicans and Democrats support updating America’s missile defenses. But low-tech surprise attacks like the one Ukraine launched against Russia this week – using inexpensive drones hidden in modest wooden huts with retractable roofs – have complicated the debate.
Why We Wrote This
President Trump’s proposed Golden Dome missile defense system is ambitious and expensive. The technology has evolved since the Star Wars days, but it still has a long way to go.
What’s a Golden Dome?
There remains some basic uncertainty about what precisely a Golden Dome is, even among specialists who describe it as a sprawling “system of systems” involving everything from space-based interceptors to dirigibles closer to Earth.
The combination of multi-layered space and land-based weapons is designed to provide a protective shield over the country by detecting and intercepting standard or nuclear missiles during flight, and potentially even before they are launched.
The name is a nod to Israel’s Iron Dome, which has been largely successful in defending against low-tech rocket barrages. Mr. Trump originally referred to his proposal as an “Iron Dome for America”; however, “Iron Dome” is a trademark owned by an Israeli defense corporation.
The “dome” idea harkens back to America’s 1983 Strategic Defense Initiative – known as “Star Wars” – that aimed to protect the U.S. “from nuclear missiles just as a roof protects a family from rain,” as then-President Ronald Reagan put it. That program was shut down a decade later amid technological challenges as the Cold War drew to a close.
Today, President Trump says that his goal, using improved technological advances, is “completing the job that President Reagan started” and, in so doing, “forever ending the missile threat to the American homeland.”
Mr. Trump estimates that the Golden Dome will take three years to complete, cost about $175 billion, and be “very close to 100%” effective. On each of these points, experts express skepticism.
How would it work?
The Golden Dome would defend against cruise missiles, which fly low, rendering them tough to track by standard radar, says Bradley Bowman, senior director of the Air and Missile Defense Program at the Foundation for the Defense of Democracies.
It could also protect against hypersonic glide vehicles. Launched by ballistic missiles into the earth’s upper atmosphere, these glide weapons detach and move toward targets at hypersonic speeds, changing course and turning wildly – maneuverability that defies conventional algorithms for projecting flight paths.
To defend against these weapons, some experts say, it’s necessary to place a “dome” of sensors and weapons in space, thus the Golden Dome moniker. “You have to get your radars up high, looking down for missiles coming in at different altitudes and different speeds,” Mr. Bowman says.
Scaling such a defense system is a challenge.
While Israel’s Iron Dome defends a nation the size of New Jersey, the U.S. would need to put some 10,000 weapons in space, for example, to counter less than a dozen North Korean intercontinental ballistic missiles (ICBMs) launched at the same time.
Sgt. David Rincon/US Army
Current U.S. missile defense systems, chiefly focused on shooting down rogue missiles from North Korea or Iran, “are designed for a very narrow purpose, one or two missiles,” says James Brown, a political science professor at Temple University, Japan.
However, even as many arms control advocates support parts of the Golden Dome plan, concerns persist over its sprawling, still-undefined scope.
“If resources are endless, then you could perhaps justify this,’’ says Mr. Brown of Temple University. “But given how much it’s likely to cost, surely there are other things that would be more deserving of these hundreds of billions of dollars.”
What would the Golden Dome cost?
A recent Congressional Budget Office report says that though top estimates for building such a program have decreased by a third – from $831 billion to about $542 billion – over the past 20 years, due mainly to lower space launch expenses – threats have simultaneously grown “in ways that could increase the overall size and cost” of a Star Wars-style defense system. Costs could also be higher due to increased sophistication and the number of intercontinental ballistic missiles (ICBMs) from potential adversaries, such as North Korea.
The Golden Dome system, which Mr. Trump says will cost $175 billion – a figure at the lowest end of the CBO estimate – has already been allocated $25 billion. That’s 2.5% of the total Defense Department budget’s $1 trillion request this year – for its initial phase. But final costs are unclear, as the initiative is currently in the conceptual stage.
As such, the proposed project is seen by many defense analysts, in Pentagon parlance, as an “exquisite” system – a term used to imply doubts about a weapon’s technological feasibility and cost-effectiveness.
Sen. Jack Reed, the top Democrat on the Senate Armed Services Committee, has called it “essentially a slush fund.”
Even supporters are quick to concede how costs are often low-balled. “I’m 34 years in this business,” Gen. Chance Saltzman, commander of U.S. Space Force, said at a Politico event last month. “I’ve never seen an early estimate that was too high.”
The Golden Dome project would also require defense budget tradeoffs, most notably around the size of the U.S. Army, including troop strength. Defense Secretary Pete Hegseth warned in an April memo that the Army must “streamline its force structure” to prioritize air and missile defense through the Golden Dome.
The technology, too, isn’t fully developed. “You don’t buy Golden Dome. You orchestrate a program that includes a lot of programs that you stick together in very technical ways,” General Saltzman said.
The prospect of building and maintaining a Golden Dome indeed remains a “daunting challenge,” according to an American Physical Society Panel on Public Affairs report, published in February.
But most agree that the United States needs to improve its missile defense.
A Golden Dome “is going to be much more costly and time-consuming than people realize. It’s incredibly ambitious,” says Mr. Bradley Bowman, senior director of the Air and Missile Defense Program at the Foundation for the Defense of Democracies. “It’s also absolutely necessary.”
Would it make the world safer?
Despite the risks defense budget cuts pose, President Trump’s impulse to build a protective shield for America is understandable, Professor Brown says.
“For all of his faults, he doesn’t seem to be a warmonger. I think he’s been taken by this quite simple idea that if missile defense works, then it could be the route to reducing nuclear weapons stockpiles,” he adds. “If you’ve got a good defense, you don’t need so much of an offense.”
The problem, Professor Brown and others say, is the view from the other side. America’s rivals see this defense as a mounting offense.
“Another way to imagine this as an American is that if tomorrow we woke up and read in the papers that [Chinese leader] Xi Jinping had just authorized a Golden Dome for China that would render the U.S.’s ability to hit China with nuclear weapons moot,” Mr. Panda says. “The U.S. would not see that as a defensive measure being taken by China.”
Indeed, Chinese foreign ministry spokesperson Mao Ning told reporters last month that the plan “heightens the risk of space becoming a battlefield.”
In this way, the Golden Dome could serve “kindling for a three-way arms race” between China, Russia, and the United States, Mr. Panda says, even as Russian President Vladimir Putin steps up development of what he calls nuclear “super weapons.’’
Such developments are “completely at odds” with President Trump’s statements that he is trying to decrease the risk of nuclear war, Professor Brown says.
“My hope is that the White House will follow the president’s instincts on denuclearization,” Mr. Panda says, “and actually find ways to mitigate an arms race.”
