Bob Bryan

Jun. 29, 2016, 11:20 AM

In the past few years, concern over immigration has skyrocketed in the US.

Amid numerous terrorist attacks, the rise of political campaigns with immigration as a central focus, and slow economic growth, worry over immigration is nearing levels not seen since the September 11, 2001, terrorist attacks.

As pointed out by Deutsche Bank's Torsten Sløk, the Migration Fear Index as measured by Economic Policy Uncertainty has spiked over the past year.

The index is constructed by taking terms related to immigration such as "immigrant," "border control," and "open borders" and seeing how many news articles include one of those terms along with a fear-related term such as "anxiety," "crime," and "worry."

Granted, this is a rudimentary guide to what people are thinking at any given time, but the spike is certainly notable considering the only time the index has been higher was during the Kosovo War and following refugee crisis.

Immigration has become a central part of the political discussion, as Donald Trump, the presumptive Republican presidential nominee, has stoked concern about immigration, blaming it as one of the reasons for economic shortcomings among the middle class and as being among the sources of the terrorist attacks in San Bernardino, California, and Orlando, Florida.

The jump in the US Migration Fear Index, however, has paled in comparison with the increase in that of the UK. After terrorist attacks in Paris and Brussels, the Syrian refugee crisis, and the Brexit campaign's heavy focus on migration, the UK index has soared to an all-time high.