{N. Korea upgrading missile site, research group says|Security Council resolutions, have intensified concern that North Korea is moving toward its goal of building a bomb small enough to be fitted on an intercontinental missile|He did not touch on whether they could be cooperating on missile and nuclear development|A successful satellite launch in December, and a nuclear test on Tuesday, both in defiance of U.N|Analysts doubt the North has yet mastered how to miniaturize a nuclear device to mount on a long-range missile and attain its goal of being able to directly threaten the United States|38 North estimates that construction at Tonghae’s new launch pad could be completed by 2016|He said it hinted at “the cozy relationship between the North and Iran as both move forward with developing weapons of mass destruction.” U.S|