When smugglers carrying deadly radioactive cesium-137 emerged from the woods near the Armenian-Georgian border in August 2014, the police were waiting. They were far from any fixed radiation detector.  But the Georgian security services learned the smugglers chose not to use the official border crossing because there was a radiation detector there — driving them right into the police’s arms on the wild border.  Had there been no radiation detector at the official border crossing, the smugglers would have passed through without detection.   

The possibility of a terrorist detonating a “dirty bomb” or even a crude nuclear bomb is one of the gravest threats facing the United States today. Yet the House Armed Services Committee is pushing a bill that would prohibit funding for fixed radiation detectors to catch nuclear smugglers – both for installing new ones and even for maintaining the ones U.S. taxpayers have already paid billions to install.  


Radiation detection is a highly imperfect line of defense. Once nuclear material has left the facility where it is supposed to be, it could be anywhere, and recovering it poses an enormous challenge. The immense length of national borders, the huge scale of legitimate traffic, the myriad pathways across these borders, and the small size and sometimes weak radiation signal of the nuclear and radiological materials terrorists might be seeking combine to make nuclear smuggling extraordinarily difficult to stop. 

But that hardly justifies giving up. From airports to bridges across major waterways to the loading stations at container ports, there are many locations where fixed radiation detectors make sense.  A balanced program to defeat nuclear smugglers must include strong security to keep material from being stolen in the first place, effective law enforcement and intelligence work, and interdiction efforts and border controls backed by both fixed and mobile radiation detectors.  These elements work together, reinforcing each other’s effectiveness. In addition to detecting stolen radioactive and nuclear material, fixed radiation detectors deter smugglers from using official borders, limiting their options and making them easier to catch.  As a military leader in Azerbaijian—which shares borders with Russia—recently argued, “to leave an unequipped border crossing is like leaving the window open.” 

For nearly twenty years, both Republicans and Democrats in Congress and the White House have invested billions in putting in place a network of thousands of fixed radiation detectors in more than fifty countries. Cutting off funding now would mean abandoning partners across the world, after years of painstaking diplomacy – and would undermine the investment already made, reducing the chance that existing detectors would continue to be used effectively. 

As much of the nuclear and radiological material smuggled to date has come from Russia—a country with hundreds of tons of nuclear weapons material spread across dozens of facilities—detecting smuggling from Russia is vital. It became even more important last year, when Russia halted nearly all work with the United States on improving the security of its nuclear stockpiles, increasing the risk of nuclear theft and smuggling.  The good news is that before the recent crisis in U.S.-Russian relations, Russia and the United States worked together to install a ring of detectors at all of Russia’s official border crossings.  The bad news is that the conflict in Ukraine has effectively erased some of those borders, and Russia’s customs union with Belarus and Kazakhstan means goods flow across those borders unchecked.  Hence, there is a clear need to install more fixed radiation detectors to patch the holes in the system already put in place.  

Beyond Russia, there is radiological material located at thousands of inadequately protected sites in more than a hundred countries.  These vulnerabilities, combined with the rise of groups like the Islamic State who are bent on mass violence and terror, make deliberately weakening defenses against nuclear smugglers recklessly negligent.   

The proposed end of funding for fixed radiation detectors would send precisely the wrong message as the United States prepares to host a global nuclear security summit in 2016. The United States should be pressing countries to keep their foot on the gas in reducing the threat of nuclear terrorism, not letting up on the effort itself. 

Cooler heads can still stop this proposal and maintain a balanced effort to stop nuclear smuggling. Senator John McCainJohn Sidney McCainGOP senators appalled by 'ridiculous' House infighting MSNBC's Nicolle Wallace, Chris Christie battle over Fox News Trump's attacks on McConnell seen as prelude to 2024 White House bid MORE (R-Ariz.), for example, now chairman of the Senate Armed Services Committee, argued in 2008 that the United States needed to “redouble” its “efforts to reduce the risk that nuclear…weapons may fall into the hands of terrorists.”  Let us hope that he and others remember that priority and maintain our investment in the full set of tools for detecting nuclear smugglers.

Bunn is a professor at Harvard Kennedy School and co-principal investigator for the Kennedy School’s Project on Managing the Atom. Tobey is a senior fellow at Harvard Kennedy School’s Belfer Center and former deputy administrator for Defense Nuclear Nonproliferation at  the National Nuclear Security Administration. Roth is research associate with the Belfer Center’s Project on Managing the Atom.