Bush unilaterally pulled out of the ABM treaty, which should have required Congressional approval, making that move potentially unconstitutional. Add it to the list.
This has led to the beginning of a new arms race. Lots of missile and bomb testing in the past 6 years. It has also raised the ire of Russia. Given the fact that Russia's basically been on the sidelines of the War on Terra, this is a stupid move.
BushCo's obstinate position against diplomacy combined with the ideological push for massive spending on a missile shield that won't work may be the ultimate failure of his tenure because many other nations feel compelled to militarize. American ability to outpace others in military spending may not last that much longer.
This article explains some of the history of the project
http://www.ciponline.org/dfd/shield.htmThis contains updated info including Eastern European installations. Also has many links concerning other aspects
http://www.basicint.org/update/MDU070529.htm