(FORTUNE Magazine) – Ravaged by decades of war and Communist misrule, the countries of what was once called Indochina (Vietnam, Laos, and Cambodia) have devolved into one of the world's poorest regions. Now, drawn by the short-term promise of natural resources and the long-term potential of a big market starved for consumer goods, a few adventurous foreigners are returning to do business. Urged on by their government, Thai companies are leading the way -- opening banks in Laos and renovating the old Hotel de Banque in Phnom Penh's business district. A Singapore company is even building a new hotel in Cambodia's capital. In Vietnam, British Petroleum and Royal Dutch/Shell have signed offshore oil exploration contracts. OTC Ltd., a state-owned Australian company, has set up a satellite link that lets Vietnam reach out and touch the rest of the world by telephone again. But Americans are still barred by law from investing in or trading with Vietnam, and Washington has been leaning on the Japanese to stay out. The U.S. slapped on its embargo when South Vietnam fell in 1975, and began urging others to join it after Vietnam invaded Cambodia in 1978. Though Vietnamese troops recently pulled out, the ban will probably continue until Vietnam helps cool Cambodia's still hot civil war. Could Indochina eventually become a golden peninsula? Maybe. Though these nations still lack such basics as decent roads and convertible currencies, political leaders are at least taking tentative steps in the right direction. Vietnam's version of perestroika, called doi moi, is encouraging local entrepreneurs to open new restaurants, video shops, piano bars, and gas stations in Hanoi. A new State Commission for Cooperation and Investment has been created to help disentangle joint venturers from bureaucratic red tape. Still, most foreign investors are likely to conclude that making money in Indochina demands more effort and time than they can afford. The best that can be said for this devastated region is that, having fallen so low, it has nowhere to go but up.