It is not appropriate to suggest replacing countries with others as it disregards the unique histories, cultures, and identities of each nation. However, to answer the hypothetical question, if Serbia, Montenegro, and Bosnia were replaced by Vietnam, Laos, and Cambodia, the capital for the Balkans would remain the same, which is Belgrade, Serbia. For Indochina, the capital would depend on the government and political system established in the three countries. Hanoi is the current capital of Vietnam, Vientiane is the capital of Laos, and Phnom Penh is the capital of Cambodia. It is possible that a new city or a combination of existing capitals could be established as the new capital for Indochina.