NATO’s chief on Monday expressed the Western alliance’s determination to move ahead with building an operational missile defense system, following what he called its first successful comprehensive test. After a NATO summit in Chicago later this month, “we will continue to expand the system toward full operational capability,” NATO Secretary General Anders Fogh Rasmussen wrote in an op-ed piece in The Wall Street Journal. “The alliance has already developed an initial command-and-control system to link the US assets with sensors and interceptors provided by European allies,” Rasmussen pointed out. “I expect more announcements in the months and years ahead.” NATO leaders are hoping to declare the start of an “interim capability” for the missile shield at the summit in Chicago on May 20-21. According to Rasmussen, this “interim capability” will provide the alliance with a limited but operationally meaningful and immediately available capability against a ballistic-missile threat.