A 2007 briefing by General Patrick OReilly, director of the US Missile Defence Agency, disclosed that the radar system would be unable to detect long-range missiles in the launch phase because it could only see in a straight line, not over the horizon. By the time the radar "saw" the missile, it would be too late to launch an interceptor in time to stop it striking its target.
The Czech radar system was the lynch-pin of George Bushs son of star wars missile defence plans, ostensibly intended to intercept missiles launched from North Korea and Iran.
Russia reacted furiously to the proposed system, which it claimed could threaten its own defences and be used to spy on its interests.
A leaked cable obtained by WikiLeaks detailing US talks with Moscow describes a briefing by General OReilly on the capabilities of the Czech radar.