Investors' equity allocations are high, not necessarily from new purchases, but from strong market performance. This passive 'drift' creates a significant, often overlooked, concentration risk. This means many portfolios are more exposed to an equity drawdown than their owners may realize, necessitating a review of diversification strategies.

Owning multiple stocks or ETFs does not create a genuinely diversified portfolio. True diversification involves owning assets that react differently to various economic conditions like inflation, recession, and liquidity shifts. This means spreading capital across productive equities, real assets, commodities, hard money like gold, and one's own earning power.

The proliferation of investing blogs has led to intense focus on US stocks. An analysis of popular sites showed 85% of ideas were US-based, with none from Australia or Japan. This saturation creates an information arbitrage opportunity for investors exploring less-covered international markets.

Mere statistical diversification often leads to concentration in market bubbles. A superior approach is "variegation"—intentionally creating a non-uniform portfolio with different industries, countries, and ballast assets like gold to build true resilience, much like a diverse garden.

Bridgewater's Co-CIO argues the winning formula of the last 15 years—concentrating capital in US equities and illiquid assets—is now a dangerous trap. He believes most investors have abandoned diversification because it hasn't worked recently, creating a risky setup that calls for a globally diversified portfolio.

The emotional drivers of FOMO (buying high) and panic (selling low) make the simplest investment advice nearly impossible to follow. A diversified, 'all-weather' portfolio protects against these predictable human errors better than high-risk concentrated bets.

While the S&P 500's 19% gain since last year seems strong, it significantly lags global performance. An ETF tracking worldwide stock markets is up 42% in the same period, with markets like South Korea and the Eurozone showing even larger returns. This indicates a potential "sell America" trend among global investors.

As the world de-globalizes and countries become more economically isolated, correlations between international stock markets decrease. This falling correlation makes global diversification more powerful and essential for investors, not less, as was the case in the 1970s.

The tendency for investors to overweight their domestic stocks is a powerful global bias. The case of Sweden is an extreme example: despite its stock market representing only 1% of world GDP, Swedish citizens invested the majority of their retirement funds domestically, irrationally ignoring 99% of global investment opportunities.