Siegfried Hecker, CISAC co-director and nonproliferation expert, writes in CTBTO Spectrum that the United States should take the lead in ratifying the Comprehensive Nuclear Test-Ban Treaty. The benefits that the United States receives in security from enhancing the international nonproliferation regime far outweigh the benefits of continuing to test the U.S. nuclear stockpile. Hecker argues that ratifying the treaty would establish an important barrier to testing and an additional means to pressure states such as Iran and North Korea to pursue a peaceful nuclear path.