For more than a century, the United States has been the world's preeminent wealth-creating machine. Now, though, the U.S. is passing the baton to its smaller competitors. Investors would be smart to follow suit by investing their money where the new millionaires are.

Getting back to even
Management consulting firm Boston Consulting Group recently released a report comparing wealth levels before 2008's financial crisis with those after 2009's global stock market rally. The initial results are quite encouraging: Globally, total wealth came in at $111.5 trillion, regaining its pre-crisis levels. The number of millionaires around the world actually increased by 14%.

The problem for U.S. investors, though, is that those gains weren't evenly distributed around the world. In particular, although North America gained the most raw wealth last year, its growth lagged behind most other regions. Japan also didn't recover as strongly, leaving it and North America still below their pre-crisis levels.

The regions that benefited, predictably, were Far Eastern countries including China, Singapore, and Hong Kong. China saw its number of millionaires rise 31% from 2008. The research company sees that trend continuing, with other emerging markets such as India likely to follow suit in the years to come.

Follow the wealth
If you're aiming to join the ranks of the millionaire class, then keeping tuned to global economic trends makes a lot of sense. In particular, if you don't have international exposure in your portfolio, you're missing out on what may be a golden opportunity.

Fortunately, you could hardly ask for better timing to make a foreign investment. Here are just a few of the factors favoring U.S. investors looking abroad right now:

  • Dollar strength. After years of endless falling, the U.S. currency has shown some real muscle so far this year against many foreign currencies, including the euro, the British pound, and even the Brazilian real. That makes it cheaper to buy assets denominated in those foreign currencies.
  • Fear in Europe. There's a lot of anxiety over the sovereign debt crisis in Europe. Yet just as in the U.S. in 2008, plenty of strong stocks have seen huge sell-offs, despite little or no connection to the underlying financial crisis. For example, European drugmakers GlaxoSmithKline (NYSE: GSK) and Sanofi-Aventis (NYSE: SNY) have both seen their shares tumble more than 15% since the beginning of the year. Yet although analysts see their growth slowing, both already trade for less than 10 times forward earnings estimates.
  • Chinese uncertainty. Similarly, many investors are worried about China. Some believe that Chinese real estate will be the next bubble, whose bursting would have a direct impact on real-estate broker E-House (NYSE: EJ) and potentially send ripples throughout the economy. But the market already seems to be pricing in such a crisis, even though it hasn't happened yet. For instance, before yesterday's big rally, Baidu (Nasdaq: BIDU) shares had lost almost 14% in less than a month. However, the company still expects to improve on its already dominating position in Chinese Internet search. (Nasdaq: NTES) is seeing amazing revenue growth and a promising future in the online gaming industry, but it's dropped 27% since March.

All of those factors are conspiring to make it a perfect time to move some of your money into foreign investments.

So how do you do it?
You can pick individual foreign stocks the same way you choose domestic stocks for your portfolio. That can be a bit more complicated, since you'll have to deal with currency translations, unfamiliar markets and regulatory frameworks, and even language barriers, in some cases. But great opportunities wait for those who look for them.

Alternatively, ETFs make foreign investing easy. A no-frills approach would combine iShares MSCI EAFE (NYSE: EFA), which gives you exposure to developed economies in Europe and Asia, with Vanguard Emerging Markets Stock ETF (NYSE: VWO), which fills in the gaps with emerging-market countries.

However you do it, don't miss out on the wealth you can make by investing abroad. If the brightest future lies over the horizon, make sure you're part of the action, instead of watching from the sidelines.