WHILE the most visible reaction after proposed reforms to US immigration laws, stalled in Congress last week, was the hundreds of thousands of mostly Latino demonstrators drawn onto the streets, behind the scenes most US business leaders were equally disappointed.

Most US business leaders and lobby groups have vigorously supported the Bush administration's push for reforms that would legalise the residency and work status of most illegal immigrants, and put many on a path to US citizenship.

There are an estimated 11 million people who live and work illegally in the US, up from an estimated 3 million in 1985.

Over recent years, despite increased border security and heavy spending on fences, aircraft patrols and fancy detection technologies, the annual inflow is estimated to have hovered around 850,000.

As these individuals have become integrated into the economy, many industries have become dependent on them.

This is particularly true of labour-intensive areas such as agriculture, low-tech manufacturing, hotels and hospitality, residential construction and domestic services, where unskilled or semi-skilled illegal immigrants often form the backbone of the labour force.

Firms in these sectors have warned of the economic disruption that would follow if laws were changed to force employers to scrutinise the credentials of would-be workers more closely, and to increase penalties on companies found to be employing illegal workers.

This would be a radical departure from the current environment, where the federal Government, more or less, ignores breaches of the immigration rules by businesses that hire these workers, in what is a tacit acknowledgement of economic reality.

But there has also been more general business support for the reforms proposed by the White House, which would have created a new category of legal guest workers, and allowed the majority of the illegals already in the US to stay and eventually become citizens if they could present a solid work and tax-paying history.