As the array of foreign missiles capable of reaching the United States grows, four Republican lawmakers are pressing Defense Secretary Chuck Hagel for assurances after a third consecutive failed test of “the only national missile defense system in place to protect the American people.”

In a letter responding to the unsuccessful test of the ground-based midcourse defense system (GMD), the four said the system “appears to have been put on ‘life support’ under the Obama Administration’s budget requests.”

The last successful GMD test took place in December 2008, when an interceptor missile launched from Vandenberg Air Force Base, Calif. intercepted and destroyed a long-range ballistic missile target launched in Alaska minutes earlier.

Since then there have been three failed tests of the system, the most recent on July 5, when an interceptor missile launched from Vandenberg AFB failed to intercept a target launched from a test site in the Marshall Islands.

The Pentagon’s Missile Defense Agency (MDA) said officials would carry out an extensive review to determine the reasons for the failure.

House Armed Services Committee chairman Rep. Buck McKeon (R-Calif.), strategic forces subcommittee chairman Rep. Mike Rogers (R-Ala.), Senate Armed Services Committee ranking member Sen. James Inhofe (R-Okla.), and strategic forces subcommittee ranking member Sen. Jeff Sessions (R-Ala.), noted that funding for the GMD system in 2008 was just over $2 billion, but that that amount had been halved by 2012 and continues to fall.

“Such funding cuts have touched every facet of the GMD program, including its maintenance.”

“While it may take some time to reach a final diagnosis of the cause of the July 5th test failure, it is already clear that President Obama’s decision to drastically cut funding for the GMD program since he came to office and to ‘curtail additional GMD development’ has drained funding available to conduct needed tests of this system,” they wrote.

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