By Sandy Murray BBC Scotland business staff

The major job losses at the Chunghwa Picture Tubes factory represented the latest blow for what used to be seen as the saviour of the Scottish economy - Silicon Glen.

The hope had been that Scotland would build an electronics industry with "critical mass" - a cluster of economic activity big enough to lure more businesses keen to share the facilities and talent already established here.

For much of the past decade, it was a success story. Major electronics manufacturers from abroad created centres across the central belt and smaller local companies thrived on providing them with components and services.

But as the world economy faltered, and the demand for high-technology products collapsed, Scotland suffered from branch-plant syndrome.

The site was once an investment flagship

The newly-established factories, often thousands of miles from a corporation's head office, sometimes found themselves first to face the axe.

Chunghwa has pointed to "current global economic conditions" as the explanation for the pull-out from Lanarkshire.

This is part of the story, but there are signs that Chunghwa as a company is starting to taste recovery.

Shares in Chunghwa have been surging in value on the Taiwanese stock exchange. Like others in the sector, it is seeing strengthening demand for its display screens.

The Scottish factory will not benefit from this success. It has been producing the old-fashioned picture tubes which are losing ground to modern flat-screen technology.

This closure, and others before it, have led to questions about the wisdom of concentrating public resources on attracting investment from abroad.

The Chunghwa story will be a lesson learned for policy-makers, at great expense

In spite of the tens of millions of pounds given, directly or indirectly, to Chunghwa, the more optimistic projections of thousands of jobs have never been fulfilled.

The Scottish Executive and the agencies working in the public sector, are increasingly focusing their efforts on encouraging businesses already here.

They hope that these businesses will be more likely to stay the course when times get tough.

Enterprise Minister Iain Gray has asked his officials to look at recovering some of the assistance which has been given to Chunghwa.

But funds returning to the public purse are likely to be small change rather than big bucks.

The Chunghwa story will be a lesson learned for policy-makers, at great expense.