幄 is a tent-like canopy, mainly in 帷幄 (a military command tent). The idiom 运筹帷幄 — 'to devise strategies within the tent' — praises masterful planning from behind the scenes.
The cloth radical on the left, a pictograph of a hanging piece of fabric. A tent is made of stretched cloth, so this radical fits the meaning. It groups 幄 with 帐, 幔, and 帷.
