Recently, North Korea claimed to have tested a fusion weapon – very unlikely due to the low recorded seismic activity – and launched its sixth long-range rocket that placed a satellite into orbit. Congressman Mac Thornberry, Chairman, House Armed Services Committee, is correct that South Korea needs the Theater High Altitude Area Defense (THAAD) and America must boost homeland missile defense and modernize its nuclear deterrent for protection. Policy leaders should take the chairman’s recommendations seriously to ensure U.S. allies and citizens are safe from potential harm.

THAAD uses a radar to detect and target incoming missile threats. The system then fires an interceptor from a truck-mounted launcher and kinetic energy destroys short- and medium-range missiles in the terminal stage of flight. THAAD is considered one of the most advanced missile-defense systems – it has successfully completed 100 percent of tests since 2005. This is why America deployed a THAAD unit to Guam to deter aggression from Pyongyang and defend the Pacific region. General Curtis Scaparrotti, Commander, U.S.  Forces Korea, has specifically recommended the system to protect Seoul from Chinese and North Korean threats – the system can counter some threats from Beijing and just about all threats from Pyongyang.

Right now, the U.S. has limited protection from intercontinental ballistic missiles (ICBMs) carrying nuclear, chemical, biological or conventional warheads with the Ground-based Midcourse Defense (GMD) System. The GMD launches ground-based interceptors (GBIs) to destroy incoming missiles in space from sites located in Alaska and California. Vice Admiral James D. Syring, Director, U.S. Missile Defense Agency, stated at a recent event in Washington that GBIs will increase to 37 interceptors in 2016 and 44 interceptors in 2017. While GMD has received criticism due to high costs and uneven success of flight tests, the system needs upgrades and more testing to increase reliability and effectiveness.

For instance, the Exoatmospheric Kill Vehicle (EKV) – which separates from the interceptor in flight – has been using the same basic technology since its inception. The Missile Defense Agency is working on a more effective EKV to increase reliability so that fewer interceptors need to be shot at a target. It is best for Washington to identify improvements and upgrade components of GMD instead of building a more expensive new system from scratch. A third missile defense site should also be built on the East Coast of the U.S. to increase warfighters’ battlespace and to increase protection from accidental or deliberate ICBM attacks.

President Barack Obama supports the modernization of the U.S. nuclear arsenal because his administration understands the critical role the nuclear deterrent of ICBMs, bombers, and submarines plays in national security. The triad provides Washington with a second-strike capability to deter nuclear attack and blackmail from potential adversaries. Allies depend on the American nuclear arsenal to provide an umbrella for protection, which reduces the likelihood new states will decide they need their own deterrent. Even though the U.S. has neglected modernization and decreased the total number of its nuclear arsenals since the end of the Cold War, other countries like Russia and China continue to modernize their strategic arsenals. Beijing is increasing the size of its nuclear force and Moscow did away with its “no first use” policy – and added the option of “de-escalatory” nuclear strikes, placing these dangerous weapons at the center of its military doctrine. It will cost a lot of money to upgrade the U.S. strategic triad, but it is necessary for Washington to deter potential threats. Those who state the strategic deterrent is too big or costly do not grasp the implications of current strategic trends.

North Korea’s claims that it conducted an H-bomb test and the fact that it launched its sixth long-range rocket demonstrate that Pyongyang has no interest in halting nuclear weapons development. Pyongyang continues to expand its nuclear stockpile and develop missile delivery systems. The international community is discussing more economic sanctions for North Korea and is attempting to convince China to play a more proactive role in eliminating Pyongyang’s deadly weapons. In the meantime, the U.S. must remain committed to its allies in the Pacific and take action to protect itself by deploying THAAD to South Korea, upgrading the Ground-based Midcourse Defense System, and modernizing all three legs of the nuclear triad.