Is Europe being set up for a fall again? In the last tech boom, European venture-backed companies caught the investment wave depressingly late and were dead in the water before they had time to show their mettle. At the same, many US VCs had already exited some of their investments by the time markets collapsed and so were, financially speaking, able to weather the storm better.

There are indications that this time round may be no different. With world debt and equity markets precariously poised, US investors have slowed down investments in the Web 2.0/social networking space. According to figures out this week from Dow Jones VentureOne and Ernst & Young, Web 2.0 investment fell in the US to $357m in the first six months of the year. This compares to a doubling of investment in Europe to $51.5m over the same period. How can we explain this apparent divergence of views?

Either European investors know something that US investors have missed or it's the other way round. In other words, it is possible that a clutch of European Web 2.0 companies has recently sprung up offering services not offered by the vast array of Stateside start-ups. But it is equally possible that US investors have sensed a coming slowdown in the sector, perhaps due to saturation and lack of exit opportunities.

Either explanation is plausible, but history suggests European investors may be in for a rough ride again.