According to Roger Cliff, a senior political scientist at the RAND Corporation, while the SM-3 would have limited effectiveness against Anti-ship ballistic missiles (ASBMs), the U.S. arsenal has a "variety of potential countermeasures" and the "kill chain" of for example a potential DF-21D attack would be so "complicated" that it would provide a "number of opportunities to defeat the attack". He also stated that unless one country integrates an "entire system of systems" to make this work, the missile itself would be pretty "useless".