This could be what really scares the market about Trump

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Not since the financial crisis have fund managers been so worried about protectionism.

In the latest Bank of America Merrill Lynch monthly fund managers' survey, protectionist risk was listed by 160 global fund managers as the second-biggest risk for financial stability, after geopolitical risk.

BofAML chief investment strategist Michael Hartnett said the rise in protectionist concerns are tied to Brexit, the immigration worries in Europe and the U.S. presidential election.