Hey Jim, your hero first got rich through a monopoly, and guess who with? The military.
I remember the phone charges were extortionate, 500 baht a month if I recall correctly, but there was no rival.
From Wikipedia:
Advanced Info Service (AIS) was given a monopoly contract by Thaksin's military contacts in 1986 and used the GSM-900 frequency band. AIS grew rapidly and became the largest mobile phone operator in Thailand