From ABC News:
"Based on statements so far, Trump's plan to remove the undocumented immigrants who have committed crimes is similar to what President Obama declared in 2014. Here's a look at some of the numbers:
How many people have been deported under Obama?
President Barack Obama has often been referred to by immigration groups as the "Deporter in Chief."  Between 2009 and 2015 his administration has removed more than 2.5 million people through immigration orders, which doesn’t include the number of people who "self-deported" or were turned away and/or returned to their home country at the border by U.S. Customs and Border Protection (CBP)."  "According to governmental data, the Obama administration has deported more people than any other president's administration in history.  In fact, they have deported more than the sum of all the presidents of the 20th century."

Oddly enough, I don't recall anyone during that time worrying about us being a walled-up fortress of fearful people.