• About 50 US Joint Staff officers were polygraphed over media leaks.
• Leaks involved reports of depleted US weapons stockpiles during Iran conflict.
• Pentagon spokesperson emphasizes taking leaks of national security information seriously.
• Investigation aims to identify and deter future leakers.

This move may indicate a significant escalation in the Pentagon's efforts to control information and deter leaks, which could have implications for press freedom and the ability of journalists to report on sensitive topics. The use of polygraph tests suggests a high level of concern about the security of classified information, which may signal a shift in the Pentagon's approach to managing leaks.