The brigadier–general was free to mentally confess that, of all the eccentric persons he had ever met, none was comparable to this product of the exact sciences.
Promotions came slowly; still, by 1844, he was a brevet brigadier general and commanding officer of the First Department, United States Army, at Fort Jesup, Louisiana.
Commissioned a brigadier general during the Mexican War, he was among the conquering Americans who followed Winfield Scott's trail from Veracruz to Mexico City in 1847.
Washington was selected to serve as Forbes's acting brigadier, and when the French abandoned and burned the fort, the main objective of his strategy for Virginia's defense was achieved.