Secretary Hagel spent much of the day following the Navy Yard shooting collecting input to help define the parameters of the review, which could be announced Wednesday, a senior Pentagon official said.
Monday's horrific Washington Navy Yard shooting, which killed 12, is the third attack in four years on US military installations at home. Active-duty or former military men were behind all three cases.
Four US Navy guided missile destroyers, along with British warships, are positioned in the Mediterranean Sea to attack Syrian military targets. It's a cat-and-mouse game, as Syria likely places decoys.