This is a question of having limited resources and needing to pick your battles.
This Birther thing strikes me as like seeing a driver with an intermittent taillight. And the driver is legally blind, reeks of alcohol, has numerous open containers in the vehicle, a suspended license, no insurance, a sack of weed on the dash, a loaded machinegun on the seat and a fresh dead body in the trunk.
But the insistence is on arguing whether or not an intermittent taillight meets the legal definition of a broken taillight.