Investing in euros is really betting that euros will increase in value against the dollar. A few years ago, this was a very secure bet. While the Cold War was current, the American dollar was the world currency of choice. It was based on the most stable economy of the world, it was steadily increasing in value, and other country’s buying of US bonds ensured the future stability of dollars.

At the end of the cold war, things changed. The European Union steadily gained prominence in the world, and sometime in the late 1990s its new currency, the eurobuck, suddenly became the world currency of choice, displacing the dollar surprisingly quickly. The European stock market was booming, between the twin effects of outsourcing and stalling American and Japanese economies. It seemed certain that Europe was the rising superpower, and quickly rivaling the U.S. economy.

Today, this doesn’t seem quite as certain. Euros seemed destined to be embraced by all of Europe – but first northern Italy, then France, and then Denmark started bucking the trend. Their own currency was being devalued by the competition against euros.

The future of the European Union itself may not be as stable as market analysts were predicting, either. A European constitution is back to the drawing boards, after being voted against by the French and the Danes. And many of the agreements made by individual European countries are starting to fall apart as economies growing in tandem suddenly start competing with one another.

Still, investing in euros may not be a bad idea. Despite the changing atmosphere around the European Union, European technologies and industries are still growing rapidly, and have tight alliances regardless of what their governments are doing. With the changed atmosphere in the U.S. in regard to foreign researchers, many are choosing to live and work in Europe instead. And Europe and South Korea seem likely seats for emerging new technologies like stem cell research.

If you’re planning on investing in euros, keep current on trade agreements between the U.S. and Europe, and watch what emerging technologies are doing. As long as Europe is more open to new technologies and is moving toward a common government, the euro will be a secure investment. When that changes, your investment may be in jeopardy.