Why did MacArthur wait for Japan to strike first?

Great historical share MAJ Dale E. Wilson, Ph.D. This is one of the better descriptions I've seen about why MacArthur held off. Maybe a good example of why Military leadership and politicians should not be tied at the hip.

Finally a plausible explaination.

Samuel E. Morison wrote in History of Naval Operations in WW2, volume III, 170, “A general alarm at Clark Field about 0830 sent most of the American planes airborne, but by 1000 the All Clear had been sounded. The crews had lunch and were resupplying their aircraft when the Japanese struck. No coast watchers or search radar signaled their approach. All but two planes were grounded when Japan struck."