Only thirty years ago, Bangkok's middle class was small and insignificant. Big business was the preserve of a handful of families.

Most of the top officials and professionals came from an old elite of noble lineages and long-settled Chinese families. Most of the population was still crowded into the shophouse areas of the old city and the Thonburi riverside. Leafier suburbs were confined to lower Sukhumvit and lower Phaholyothin, where houses were hidden behind high walls like medieval castles. There were still paddy fields between the city and Don Muang Airport, orchards blanketing Thonburi, and market gardens in Sathupradit. On Bangkok's streets there were few cars that did not belong to a company, government office, or international agency.

From then onwards, the middle class grew like a mushroom. Development strategy switched away from increasing agricultural exports to force-feeding industrial growth. The fact that Thailand had been a frontline state and teetering domino in the Cold War faded from memory. Foreign firms arrived in a trickle and then a flood. The expansion of the city shifted from a crawl to a spurt. University expansion in the 1970s produced a flood of new graduates in the 1980s. The city became home to a large new group of business managers and executives, to many more prospering small and medium businessmen, to an expanded cadre of senior technocrats, and to a range of new professionals from lawyers to interior designers. They burst out of the old family homes and colonised the swamps of Pattanakarn, the orchards of Thonburi and the paddy fields stretching north from Lad Phrao to the Rangsit canals. After the 1991 Anand government liberalised markets, they bought cars to commute to work and to show off their prosperity.

The overwhelming majority of this new Bangkok middle class were descendants of the Chinese migrants who had arrived in Siam between the 1870s and the 1940s. After the Chinese revolution of 1948, these families were stranded in Thailand and intent on making a success in their new home. They spearheaded the surge of the urban economy and enjoyed its benefits. They flooded into the new educational opportunities, both in Thailand and overseas. When these families transited into their second and third generations, more of the children broke away from the kongsi family business and made their own way as managers, professionals, teachers, lawyers, policemen, models, actresses and even rock stars. They intermarried with Thais and with foreigners, but the overwhelming mass of families in the new middle class could trace some Chinese heritage.

In the middle of the great boom of 1986-96 there was a cultural transition: this Chinese heritage became a focus of legitimate pride. Television dramas celebrated the role of the Chinese immigrants that had been left out of the history books. Chinese language teaching boomed. How-to books re-educated those who had forgotten their heritage. The celebration of Chinese New Year became showier. The pan-Asian and Eurasian faces faded from the fashion spreads and television screens, replaced by porcelain dolls. This cultural transition was an enormous achievement for a country where there was still reason to complain about subtle and unsubtle forms of discrimination as recently as the mid-1980s.

This new middle class grew with the globalisation of the Thai economy and seemed to appreciate that fact, even celebrate it. A spell in a US university, however short and perfunctory, was the required finishing touch for a proper education. The package of goods required for the new middle class lifestyle - house, car, appliances, foreign holiday - was copied from Western models and disseminated through advertising. The language of modern commerce and retail was English. No product could hope for success with a Thai brand name. Even locally owned and manufactured goods had to conform. English words monopolised the signage in the new palaces of consumption, and littered the scripts of advertising. While a few businessmen and officials might try to promote economic nationalism, middle-class consumers were fanatical anti-nationalists.

If there was any problem, it lay in the gulf between aspiration and economic reality. Most middle-class incomes were modest. Large-scale commercial success was concentrated among some 150 families. The managers with high-earning jobs in multinationals were a minority. In the bureaucracy, even the most senior officials still earned pittances, and their spouses often had to work in the commercial economy.

Middle-class families could scrape by because many living costs were low. Government spending was concentrated in the capital, providing better infrastructure and public services than elsewhere. Education subsidies were skewed to the tertiary level. The systematic neglect of the rural economy ensured a supply of cheap food and cheap labour.

The political priority for the middle class is to maintain the economic growth that underlies rising prosperity. Increasingly, the middle class feels that requires political stability, however that is achieved. But at the same time this globalised middle class needs to feel accepted and respected in the international landscape. To gain that acceptance, the country has to appear to be a democracy, as that has become the international standard. Only ex-communist states are still exempt. That means having a parliamentary system, conforming to some minimum standards for the rule of law, and getting rid of unacceptable practices such as human trafficking, virtual slave labour and a bloated sex industry.

Everywhere in the world, middle classes feel vulnerable to threats from above and below. The Bangkok middle class has the added insecurity of being so new and economically vulnerable. It would rather not have to choose between prosperity and democracy. It hopes to muddle through with "managed democracy" as a gift from the generals. The muddle class.