In an era when America’s enemies test our resolve and our own intelligence community may be leaking classified information, one thing remains clear — President Trump and his national security team are fighting back. Washington was rocked this week when a preliminary, unvetted Pentagon memo was leaked, suggesting U.S. airstrikes on Iran’s nuclear facilities barely dented Tehran’s ambitions. But the so-called “intelligence” — drawn from a single day of post-strike reporting and lacking input from the CIA or NSA — has been decisively discredited. Now, as federal agents scour the corridors of power to find the whistleblower-turned-saboteur, the White House,...