A year ago, ECB paper by Georgiadis, Georgios and Gräb, Johannes, titled "Growth, Real Exchange Rates and Trade Protectionism Since the Financial Crisis" (ECB Working Paper No. 1618. http://ssrn.com/abstract=2358483) looked at whether the current evidence does indeed support the thesis that "…the historically well-documented relationship between growth, real exchange rates and trade protectionism has broken down."
Looking at the evidence from 2009, the authors found that "the specter of protectionism has not been banished: Countries continue to pursue more trade-restrictive policies when they experience recessions and/or when their competitiveness deteriorates through an appreciation of the real exchange rate; and this finding holds for a wide array of contemporary trade policies, including “murky” measures. We also find differences in the recourse to trade protectionism across countries: trade policies of G20 advanced economies respond more strongly to changes in domestic growth and real exchange rates than those of G20 emerging market economies. Moreover, G20 economies’ trade policies vis-à-vis other G20 economies are less responsive to changes in real exchange rates than those pursued vis-à-vis non-G20 economies. Our results suggest that — especially in light of the sluggish recovery — the global economy continues to be exposed to the risk of a creeping return of trade protectionism."
One thing to add: the above does not deal with trade-restrictive policies relating directly to financial repression, such as outright regulatory protectionism of incumbent domestic banks and asset managers, or direct and indirect subsidies pumped into the incumbent banking system.