Goldman Sachs (GS) private wealth advisors just gave its wealthy clients the same advice it has for the last 10 years — stay invested in U.S. stocks.

"We have had a strategic overweight to US equities relative to market capitalization-weighted benchmarks for the last ten years, and this overweight has served our clients well," Sharmin Mossavar-Rahmani and Brett Nelson wrote in their 2019 outlook, a 102-page report entitled "American Preeminence in a Rattled World."

The note was circulated to Goldman’s Consumer & Investment Management Division, which has recently combined the firm’s upstart consumer lending and savings business, Marcus, with its long-time asset management business that manages more than $1 trillion dollars for institutions and ultra high-net-worth individuals.

The recommendation of overweight U.S. stocks dates back to 2009, during the height of the great recession. The firm has remained overweight U.S. equities ever since, and to date, it's been a good bet.

Since the trough in March 2009, U.S. stocks have returned about 355% (16% annualized) compared to 169% (10.2% annualized) for non-U.S. developed markets and 161% (9.9% annualized) for emerging markets, Goldman noted. Even with 2018's -4.4% performance, U.S. equities outperformed other markets, with non-U.S. developed markets returning -10.5% and emerging markets -14.2% for the year.

"We believe this strategic overweight is still warranted. While the U.S. is not immune to developments beyond its borders, the country is better positioned to weather future storms than virtually any other. It is also sufficiently resilient to absorb uncertainty from within."

"The U.S. remains preeminent, and its institutions are stronger than any one president or administration.”

In the note, Goldman recognized that the current levels of angst among investors hasn't been present since the early stages of the global financial crisis. Interestingly, this angst is happening against a backdrop of the strongest GDP growth in a decade, robust earnings growth, the lowest unemployment rate in 49 years, and core inflation at 2%.

That said, investors are worried about the end of a decade-long economic expansion, a slowdown in Europe, Japan, and China, volatility in equity markets, rising interest rates, and a trade war. There's also uncertainty stemming from the Trump Administration, including the investigations, high cabinet turnover, and the president's comments about Fed Chair Jay Powell.

Goldman, however, reminded its clients that the U.S. had faced similar challenges in the past.