William Johnstone 
Smoke From The Ashes [EPUB ebook] 

The planet is at war. Hawaii, the American fleet at Pearl Harbor, and the Panama Canal have been destroyed in sudden sneak attacks. All of South America has been conquered by the invading Japanese, under the rule of High General Hiro Wakisaki. It is six long months before the Free World can muster a response…and Hawk Hunter, "The Wingman" is at the fore. But driving the Japanese out is not the only problem Hunter must solve. Buried deep in the Falkland islands, scientists labor over a superbomb for a man with one goal-the destruction of the United States!