"The immigration officer at the airport in Saigon slid my passport over the scanner at his desk. After consulting his monitor, he remarked in English, 'Welcome back, Lieutenant.' I answered in Vietnamese, 'Thank you, Captain.' Our eyes met. He dipped his head and smiled. I entered his country, stamped passport in hand, exhilarated at what lay ahead." -Vietnam, Full Circle. Forty years after serving as the only American combat adviser in a...