blinow61/iStock via Getty Images Introduction Index investing is great - especially if you're betting on the United States of America. Including dividends, over the past ten years, the S&P 500 has returned 235%, which translates to a 12.9% CAGR. During this period, the all-world (ex-U.S.) MSCI ETF (ACWX) returned 44%, which shows the massive benefit of investors investing in the United States. Data by YCharts In fact, the past 15 years have been exceptionally good for S&P 500 investors, as the index perform ...