AlHijjah 20, 1432, Nov 16, 2011, SPA -- The United States has joined NATO's cyber defense research center in Estonia that works on ways to combat cyber attacks, as AP reported. The United States will help fund the center, and its scientists and cyber defense experts will be able to both study and teach at the center's premises in the Estonian capital Tallinn. The U.S. Embassy in Estonia said Wednesday that Poland was also joining the center, which now will have 10 members.