Last week, I wrote a column in the New York Post, questioning the Obama administration’s proposed plan for missile defense in Eastern Europe which will replace the Bush-era ground-based interceptors (GBI) in Poland and radar in the Czech Republic. I especially questioned the ability of the new Obama system to defend the United States against an Iranian ICBM until their land-based SM-3 comes on-line around 2020.

This Saturday, the Director of the Missile Defense Agency, Lt. Gen. P. O’Reilly, responded, writing in part:

Contrary to Brookes’ assertion, with our long-range interceptors currently deployed in Alaska and California, we already have the capability to defend the United States, including the entire East Coast, from a potential Iranian ICBM attack.

While we’re happy the General took time to respond to my assertions, we respectfully disagree.

The fact is that while the GBIs put in place by the Bush administration in Alaska and California (to defend against the North Korean nuclear and missile threat) have the ability to shoot down an Iranian ICBM targeting the US East Coast, these missiles are operating at the outer-edge of their performance envelope.

In other words, if the west coast GBIs could handle an Iranian ICBM, there never would have been a need for a European missile defense system for countering long-range missiles directed against the U.S. Indeed, the Bush and Obama administrations seemingly agree on this point since both decided to build a missile defense system in Europe, albeit on different time tables. (Bush would have deployed in 2013; Obama in 2020).

Moreover, relying on the West Coast GBIs takes away the “shoot-look-shoot” option until the SM-3 Block II-B interceptor can shoot down an Iranian ICBM in the ascent phase of flight, which otherwise would provide for a European-based GBI to take a shot at an incoming Iranian ICBM, to then look to see if it hit the missile, and if it didn’t, would allow for the Alaska and California sites to shoot it down as a last resort.

But without a European missile gauntlet to run, the West Coast is the first and last resort at the moment for an Iranian ICBM. Unfortunately, that’s not the defense-in-depth we need against the growing Iranian nuclear and ballistic missile threat.