The report, requested by Congress, concludes that upgrading the current system will "will take time, money and careful testing, but unless this is done," the missile defense shield "will not be able to work against any but the most primitive attacks."
The program has cost upwards of $35 billion and it has not successfully intercepted a test attack since December 2008, and only then, critics contend, under controlled conditions far less complex than reality.
Despite failing to achieve much success, the missile defense umbrella, centered at Interior Alaska's Fort Greely, has dodged budget cuts even amid increasing alarms over the country's deficit and calls to reduce spending.
The council said that since the system was developed and deployed with limited, comparatively unsophisticated threats from North Korea, it has shortcomings against "even modestly improved" North Korean and potential Iranian missiles.
The council reccommended replacing the interceptors' current Raytheon warheads with "heaver, more capable" ones with improved on-board sensors. The most advanced Raytheon warheads cost about $39 million apiece, according to the report.
Alaska's Fort Greely is home to 26 interceptor missiles, and Brandenburg Air Force Base in California is home to four.
Read more about the report, here.