America faces a growing missile threat from abroad along with the prospect of huge defense cuts. Something's wrong with this equation.

Speakers at the annual Space and Missile Defense Conference in Huntsville, Ala., outlined the extent of that threat, and they agreed that robust missile defenses are crucial. But with the tight fiscal environment and defense programs on the chopping block, this task will be more difficult. And America isn't adequately protected as it is.

Gen. Patrick O'Reilly, director of the Missile Defense Agency, said more than 32 countries now possess ballistic missiles. He raised concerns about the proliferation of anti-ship missiles and an increase in ballistic-missile production facilities.

Anti-ship ballistic missiles, or ASBMs, pose a significant threat to Navy warships and to international freighters traveling through strategic "chokepoints" such as the Strait of Hormuz. An ASBM moves considerably faster than a conventional anti-ship missile, and it is far tougher to kill. They can be fired from stationary sites or road-mobile units miles away from shipping lanes. Road-mobile missile units are difficult to detect, even by satellites.

O'Reilly said ASBMs had been "tested" and "ships had been sunk." He was almost certainly referring to Iran's successful test of an ASBM — a Fateh-110 with improved guidance. It marks a step forward for Iran, yet lacks the sophistication of China's new ASBM, the Dongfeng-21D (DF-21D).

The Pentagon's latest annual report on China's military progress says the DF-21D is meant to prevent the United States from operating effectively in the western Pacific. The report also says China is improving its strategic missile forces and may be developing a new multi-warhead "road-mobile ICBM." Could this help explain China's increasing assertiveness in regional disputes?

Then, of course, there's the potential missile proliferation arising from upheaval in the Middle East. Uzi Rubin, an expert on Iran's ballistic missile program, said hundreds, if not thousands, of missiles are in Iran, Syria, Libya, Egypt and Yemen. And, he warned, Venezuela — not far from the United States — could join that list. Iran and other rogue states, meanwhile, are always working to develop longer-range capabilities.

Another threat we can't afford to ignore is an electromagnetic pulse attack. An EMP is produced by a nuclear weapon detonated at a high altitude. This underscores the need for missile defense — a ballistic missile is the most effective means of delivering an EMP weapon. A successful attack could decimate America's electrical infrastructure and cause a catastrophe such as a large urban blackout — or worse.

A missile delivered to produce an EMP wouldn't have to be launched from 5,000 miles away. Short-range missile can be placed on cargo vessels off the U.S. coast to launch a missile at the homeland (the "Scud-in-the-bucket" scenario).

In 2004, a congressionally mandated commission found that an EMP attack is "one of a small number of threats that has the potential to hold our society seriously at risk and might result in defeat of our military forces." Five other commissions and major government studies have independently concurred. Despite this, there has been a bipartisan failure to address this threat — and virtual silence from the Obama administration.

A Scud-in-the-bucket EMP strike could be followed by cruise missile attack. A cruise missile could be fitted with a biological or chemical spray unit. If these missiles have terrain-mapping capabilities, they can be guided around like an unmanned aerial vehicle.

Then there's Russia, with whom the U.S. has supposedly "reset" relations. It just unveiled the Club-K, a container-based cruise missile for sale on the international market. This cruise missile is hidden in a "shipping container" that disguises the transporter-erecter-launcher for the Club-K missile.

Iran and other state actors are potential customers. It could also fall into the hands of terrorists.

The U.S. needs a comprehensive missile-defense system to counter these existing threats and stay ahead of emerging ones. The administration's approach of funding "just enough" missile defense may be too little, too late, especially if further cuts lay ahead.

When it comes to defense, it's better to prepare than repair. Let's turn this wrong-headed equation around.

Owen Graham is research and operations coordinator in the Allison Center for Foreign Policy Studies at the Heritage Foundation.