In comparing the dismal situation in Thailand to Vietnam, Chuck leaves out one very important historical element. This is the unrelenting pressure of the United States and other imperialist countries to destroy all forms of socialist property relations in Vietnam. The main form this has taken is economic blackmail. Unless Vietnam went along with privatization, it would not be able to secure loans and credit.
If the United States had respected the victory of the Viet Minh in 1954 at Dhien Bhen Phu and allowed Ho Chi Minh to take power peacefully, another development route might have unfolded in Vietnam. It is possible that for an extended period--until the collapse of the Soviet Union--, the Vietnamese might have developed along more egalitarian lines. As it turned out, the victory over the United States coincided with the collapse of the Soviet Union roughly and Vietnam was forced to curry favor with the West in order to survive.
This is one of the reasons I find discussion of political institutions fairly irrelevant. Chuck says, "Now, how are these appearing as a legacy to a collapsed command, or top-down authoritarian but theoretically communist political-economic structure? Are these not the same problems that are befalling Indonesia or Thailand, or the Philippines, mostly current or former fascist or military dictatorships, filled with a sea of greedy foreign capitalists?"
This really does not capture the essence of the problem. Authoritarian political structures are not the cause of corruption, inequality and greed. Capitalism is. The sort of social rot that you find in Vietnam today has been around for decades in "democratic" countries in Latin America such as Mexico, Argentina and Brazil. The American victory over Vietnam, China and the former Soviet Union has consisted of this very achievement: turning the communist world into third world banana republics.