"Assistant for Israeli missile defense occupies an increased percentage of MDA’s budget," the report stated.
The report’s primary author, Thomas Karako, explained that "US programs tend to get cut as a kind of bill-payer for a larger Israeli program."
The result of MDA’s growing foreign assistance to Israel "puts US missile defense and Israeli missile defense in competition," for the same limited funds, the report noted.
The United States has been assisting Israel in developing and procuring a number of missile defense systems including Iron Dome, David’s Sling, and David’s Arrow.
Between 1998 and 2011, MDA foreign assistance to Israel accounted for 1 to 3 percent of the agency’s budget. By 2014, the Missile Defense Agency was spending 5.5 percent of its budget, or $729 million, on the Israeli systems.
The CSIS report suggested the United States may "renegotiate the terms" of US military aid to Israel when it expires in 2018.
The renegotiation would involve budgeting strategies to shift the financial strain off of MDA, as the agency faces increasing demands amid a shrinking budget.
The MDA came into existence in 2004 following the US unilateral withdrawal of the 1972 Anti-Ballistic Missile Treaty with Russia.