Some of the praise being accorded the late Brent Scowcroft is deserved. As national security adviser to President George H. W. Bush, the unassuming Scowcroft was a voice for relative reason and moderation (compared to the neoconservatives who would follow him), as the USSR imploded and U.S. forces chased Saddam Hussein out of Kuwait.

But few pundits commenting on Scowcroft's legacy are likely to raise an awkward, but important, question that haunts me. It is of such consequence that it belongs in his obituary – and his eulogy. Scowcroft knew the attack on Iraq was not only a war crime but a reflection of insane hubris. Why didn't he join his voice to the 30 million people in 800 cities who demonstrated against the war on Feb. 15, 2003, five weeks before the invasion?