Hoover signed the disastrous Smoot-Hawley Tariff in June 1930, which destroyed the global trading system and dried up the flow of international capital.

FORBES: Fact and Comment

As the economy recovers, the country should move forward to realize bilateral and regional agreements, enhancing the international flow of goods, services and capital.

WSJ: Lloyd Blankfein: The Business Plan for American Revival

The villains of the Depression were the trade-killing, international-capital-flow-strangling Smoot-Hawley Tariff, an overly tight monetary policy and a catastrophic tax increase.

FORBES: Fact And Comment