There has been plenty of speculation during the last 2 years that we’re in a tech investment bubble. It seems every blogger is trying to “call it”.

It hasn’t burst yet and if AirBnB’s $112 million round of funding announced today is anything to go by, it ain’t going to burst any time soon.

Lets pretend the US dollar is going to continue to fall in value. You have an appetite for some risk and you’re watching your dollar denominated wealth dwindle away.

You could invest in bonds, but we all know that’s not very chic right now since even sovereign debt defaults.

You could buy currency, but just when you thought the Euro was safe, turns out half the Eurozone is in crisis and the charter doesn’t even have a clause for a member state defaulting. It “just wan’t supposed to happen”.

You could buy gold, but that looks like one hell of a bubble waiting to burst. [Although my prediction is that it will keep rising until early next year]

Hey what about Treasury Bonds. Well we already had that conversation about August 2nd earlier today, so forget that.

What about commercial or private real-estate. History has shown that has always been a safe investment …if you exclude recent history.

All this makes the US software sector look extremely attractive. Even *gasp*, startups!

Software companies make more money if the dollar falls. For example Google’s Q2 2011 international revenue made up 54% of the total and is increasing. If the dollar falls, expect Google to bring back the free food and tea trolley.

Software is not as affected by rising interest rates (which are coming) as, for example, companies that need to borrow big to finance land, oil rigs, multi-year construction projects, etc.

The software labor force is completely dynamic. Software developers can work remotely and many companies (like WordPress) have entirely distributed teams. So if India or China gets expensive, we’ll just move it back on-shore. But more importantly, because software labor can be based anywhere it is a much more efficient market than running a US based law firm for example.

The target market is also dynamic and can quickly be switched from one country to another. Unlike brick and mortar businesses, switching from selling in the UK to China simply requires a team of translators and to stop spending ad money and resources on the country in question and divert is somewhere else. No physical stores to shut down, no plant to move, no warehouse to dispose of.

And of course once you’ve written the software, the ongoing cost of running a software company is not much at all. Sure you need to keep innovating, but if the company stops writing software tomorrow the revenue keeps flowing.

The US has a track record of being the best at software. It’s rare to see a viable foreign competitor for the likes of Google, Facebook, Microsoft, Oracle, CA technologies, IBM, Accenture etc. I’m not discrediting awesome companies like SAP, but they are rare.

Companies like AirBnB, Facebook and Groupon represent a new breed of software company that is more efficient, nimble and profitable. They don’t require a on-the-ground sales team like IBM, Microsoft and Symantec. The team can be based anywhere, their server resources are distributed across the globe and all their revenue and costs are completely dynamic and distributed and can adapt continually to the rapidly changing environment.

In the current investment and risk environment, software startups are, understandably, just about the sexiest thing since, well, this: