In a surprising announcement, it seems that the United States may give up plans to put RADAR sites and/or interceptors in Poland and the Czech Republic. These sites would have been ideally suited to track and intercept ballistic missiles launched towards the United States from Iran. This is a reversal of the position President Obama adopted in April, when he gave a speech in Prague. The most plausible reason for the shift is an accommodation with Russia, which has always staunchly opposed US ballistic missile defence (BMD) plans, and which holds key levers when it comes to Iran and nuclear technologies. Notably, the sites in Poland and the Czech Republic would not be especially well placed to aid in the interception of Russian missiles, which would anyhow be too numerous and sophisticated to be plausibly neutralized through a BMD system.
The shift probably signals both the resurgence of Russia as a regional power and the decline of American flexibility that has accompanied ongoing involvement in Iraq and Afghanistan. The US may also be reckoning that it is a better strategic move to try to block Iranian acquisition of nuclear weapons, with Russian help, than to try to field a system to destroy deployable versions of these weapons if and when they exist. Iran’s successful satellite launch in February suggests that they could develop nuclear-capable missiles with a long-range capacity, provided they are able to sufficiently miniaturize their nuclear weapons: an undertaking that proved very challenging even for the United States.
While Poland and the Czech Republic are usefully positioned between Iran and the east coast of North America, Japan is best positioned between North Korea and the west coast. Given the strength of the US-Japanese alliance, and the domestic concern about North Korea and China in Japan itself, it seems likely that the Pacific version of the BMD system will continue to develop. When I visited USNORTHCOM, the US Strategic Space Command, and NORAD, all of their missile defence examples concerned North Korean launches.
[Update: 4:24pm] To clarify the above, it seems the American plan was to put X-band RADAR facilities in the Czech Republic and ten SM-3 interceptor missiles in Poland.