Improving the agility of the Defense Department's acquisition system over the next decade is the Pentagon's single biggest economic challenge, according to a DOD official charged with assessing the performance of major weapons programs. Without more nimble ways to acquire high-tech arms, the department could be outpaced by future national security challenges, said Gary Bliss, the director of the department's performance assessments and root cause analyses office (PARCA). DOD acquisition chief Frank Kendall's new Better Buying Power 2.0 guidance is...