WASHINGTON — The Pentagon’s Ballistic Missile Defense Review is underway and lawmakers, through both the House and Senate defense policy bills, are signalling the direction they want to go when it comes to developing the future defense architecture against both regional and homeland missile threats.

Both the House and Senate place a heavy focus on the future direction and modernization of the Ground-Based Midcourse Defense System (GMD) but also turn some attention out of the terrestrial sphere and into space.

Motivation is strong both in the Pentagon and on the Hill to ensure the United States is making the right decisions now on how best to defend against proliferating ballistic missile threats.

Since the release of the House and Senate draft 2018 National Defense Authorization Acts, the missile threat from North Korea has reached new levels, with the country testing an Intercontinental Ballistic Missile, which analysts said showed the capability to exceed 10,000 km in range for the first time. That range is a distance capable of potentially threatening not just the West Coast but the East Coast.

Vice Adm. Jim Syring, the then-director of the Missile Defense Agency, following a successful test in May of the GMD system designed to defeat ICBM threats from North Korea and Iran, said the performance of the system allows the U.S. to outpace the threat from North Korea at least through 2020.

Yet, Syring told the House Armed Services Subcommittee on Emerging Threats and Capabilities that he was concerned with the ability for the U.S. to continue outpacing the threat as North Korea rapidly grows its capabilities.

The Terrestrial Strategy

The Senate Armed Services Committee’s version of the defense policy bill focuses heavily on how to deepen the GMD system’s bench.

The GMD system, by the end of the year, will have 44 interceptors buried in the ground at Fort Greely, Alaska, and Vandenberg Air Base in California.

And MDA is working to improve the overall reliability of the system including redesigning the Exoatmospheric Kill Vehicle (EKV) on the Ground Based Interceptors (GBIs), which has struggled in past tests.

“As the threat from adversaries’ missiles becomes more sophisticated and complex, the committee acknowledges that expanding the GBI fleet beyond 44 is just one option for addressing such a threat,” the committee writes, “but would need to consider where additional GBIs could be deployed and the infrastructure costs to do so.”

The committee said it will take into account any recommendations made regarding the GMD program put forward by the BMDR, but “unless otherwise directed by the BMDR,” it wants to direct the Pentagon to increase the number of GBIs from 44 up to an additional 28 and put them wherever missile fields are capable of supporting additional interceptors.

Additionally, the committee would recommend stockpiling another 14 GBIs.

The committee also wants a report on options to increase the capacity of the GMD system by up to 100 GBIs that would include locating potential sites for the added infrastructure.

Much of the language comes directly from a bill submitted by Sen. Dan Sullivan, R-Alaska, on “Advancing America’s Missile Defense Act of 2017.” The bill takes into account a 2013 study on homeland missile defense that said the most cost-effective way to beef of homeland defense would be to add more interceptors.

The Clinton Administration at one point had a plan on paper to have roughly 250 interceptors.

An environmental impact study in 2000 determined the site at Fort Greely could have up to 100 GBIs without experiencing possible environmental mitigation delays.

In another section of the bill, the SASC included a provision that asks the defense secretary to consider accelerating the capabilities prioritized in the BMDR to include the Redesigned Kill Vehicle, the Multi-Object Kill Vehicle, the Configuration-3 booster, a space-based sensor layer, boost phase sensor and kill technologies and additional ground-based interceptors.”

The SASC also wants to ensure the GMD system is tested at least once each fiscal year and as part of that testing campaign include possible acceleration of the RKV, the MOKV, the configuration-3 booster, unmanned aerial vehicles that utilize directed energy and space-based missile defense sensor architecture.”

The House Armed Services Committee had similar language encouraging the continued development and investment in modernizing and improving the GMD system.

According to Tom Karako, a missile defense analyst at the Center for Strategic and International Studies, the congressional language this year represents a “palpable sense” that as the threat continues to evolve and grow, “we need to grow and outpace the threat along with it.”

Yet, the way to do that may not be a question of capacity but of capability and reliability of the current system, he said, and Congress also seems to support that.

And while there’s an obvious focus on ensuring a reliable and robust ground-based system, Congress is pushing for space-based missile defense on both sides of the Hill as well.

Looking to Space

Gaining space-based capability may be more critical than anything that can be done to improve the system on the ground when it comes to outpacing the threat, according to Karako.

Space-sensors increase the lethality and effectiveness of GBIs, “but also adds to the lethality and effectiveness of every other element of the BMDS” such as the Patriot missile defense system, the Terminal High Altitude Area Defense system and the Aegis system, he said.

In 2013, an Aegis Standard Missile-3 Block IIB fired on the basis of tracking from space, using a satellite, “and as a result dramatically increased its defended area because the defended area is a function of the radars and where we are right now is the radars, the missile basically has longer legs than the radars do,” Karako said. “Our defended area is held back not by the missile but by the sensors.”

In their mark of the defense policy bill, House lawmakers want the Pentagon to quickly produce a space-based missile defense strategy.

The strategy would lay out the plans of the MDA, the U.S. Air Force and other agencies to develop a space-based sensor layer for BMD that provides precision tracking data of missiles beginning in the boost phase and continuing throughout subsequent flight regimes among other capabilities.

And House lawmakers also call for a space test bed for space-based ballistic missile intercept.

The Senate side included a provision that would require the MDA to develop “a highly reliable and cost-effective persistent space-based sensor architecture capable of supporting the ballistic missile defense system.”

The SASC also recommended funding the MDA’s request of $27.5 million on its Unfunded Requirements List to support the development of the space-based sensor architecture.

Each of the past five administrations have had a space-based sensor layer as a critical component of its missile defense architecture on paper. But it’s never gone beyond that, usually dampened by bigger priorities and shrinking budgets.