Members of the South American trade union Mercosur met Nov. 17 to discuss possible responses to the world economic slowdown triggered by the U.S. financial crisis. Mercosur members Argentina, Brazil, Paraguay and Uruguay appear to have come to an agreement — to be fully ratified in December — to raise the union’s common external tariff on a number of specific items. The decision raises the specter of previous economic downturns that were wildly exacerbated by protectionist measures that not only failed to foster domestic industries, but also set off a dangerous spiral into economic ruin. (The Great Depression comes to mind.)

Mercosur’s proposed tariff increases are aimed at a set of specific items, including wine, peaches, dairy products, textiles, leather goods and wood furniture, according to reports by MercoPress. Argentina has expressed concern over an increase in imports of manufactured goods from Brazil that has been facilitated by a dramatic drop in the Brazilian real vis-à-vis the Argentine peso, which Argentine authorities have tried to keep pegged to the dollar. Argentina has been pursuing a number of measures to unilaterally raise tariff and non-tariff barriers to goods, such as increasing licensing requirements for and delaying the entry of imports, in an effort to protect its domestic industries from the global economic downturn. The idea is very simple: If you raise the cost of imports, you can stimulate demand for domestic goods and potentially protect jobs (and thus prevent social unrest).

But the reality is much more complicated and much less promising. Take, for instance, one of the most extreme cases of protectionist policy in modern economic history: the Smoot-Hawley tariff regime, enacted by the United States in 1930. Despite the fact that the United States had emerged as the world’s pre-eminent industrial power in the wake of World War I, a drop in commodity prices spurred a great outcry on the American domestic political scene as agricultural groups called for an increase in tariffs to protect their livelihoods. Seeing a receptive attitude in the Congress of that era, other industries began calling for tariff increases across the board.

The movement toward protectionism was cemented into place when U.S. President Herbert Hoover signed the Smoot-Hawley bill into law, causing a cascade of reactive protectionism from countries around the globe. The net effect was to reduce global trade from $35 billion to $12 billion between 1929 and 1933. The utter collapse of global trade can be credited with turning a global depression of the late 1920s into the Great Depression of the 1930s. This was certainly an extreme case, but it is a warning that Argentina in particular should consider carefully.

It wasn’t very long ago that Argentina went through its own economic travail in the wake of turmoil that culminated in the debt crisis of 2002. That downturn is still fresh in the minds of Argentines as they recall the chaos that plunged nearly 60 percent of the urban population into poverty and sparked bloody riots. The Argentine government’s penchant for protectionism has gone through several iterations in the wake of that crisis. Price controls the government enacted on the domestic market made it impossible for the agriculture industry, for one, to make a profit or even recoup costs by selling goods in Argentina. The government then attempted to raise taxes on exports such as soybeans to around 45 percent. Failing that, the government has gradually shifted to tariff and non-tariff barriers on goods.

The strategy is to reduce the impact of economic shifts on the Argentine population as a way of maintaining political support while finding new sources of tax revenue — sources that don’t burden working-class Argentines — to maintain increasingly burdensome government spending. The move toward raising Mercosur’s external tariff in the wake of the global downturn is the next logical step for Argentina. It is nowhere near the extremes of something like the Smoot-Hawley tariff for a couple of reasons. One, it appears (for the moment) to be limited to a relatively short list of items. And by enacting the measure within the bounds of Mercosur, Argentina and Brazil have at the very least maintained access to each other’s markets, so they are not limited to merely their own domestic demand levels. On the other hand, it is important to keep in mind that once tariff protections are enacted, it is extremely painful and politically difficult to lower them — especially for a state like Argentina, whose labor unions are quite powerful and whose government policies are built around protectionism.

It is safe to say that once these tariffs are raised, it will take some time before they can be lowered again. This loss of flexibility will reduce the Mercosur states’ ability to recover from the economic downturn once the rest of the world begins to turn the corner. While Brazil maintains a reasonably large industrial sector and a pool of government-controlled capital that will help it pull through the crisis, the situation in Argentina is looking increasingly delicate. It is exactly this kind of protectionist measure, isolationism, that can tip a country over the edge of economic peril into economic catastrophe.