The thought of securing the United States’ borders is appealing and makes sense to quite a few people even though, historically, this idea has fallen flat. But, now with the presidential election brewing, this seems to be a hot debate between candidates.

The border between the U.S. and Mexico spans approximately 2,000 miles, from California to Texas with illegal immigration, drug trafficking and other security breaches being issues of growing concern for years. Construction of the first “border wall” began in 1993 between San Diego and Tijuana, but 13 years and $39 million dollars later, only 14 miles of the fence has been completed, with the remaining 3.5 miles of fencing estimated to cost another $35 million.

Then came the debate of whether it would be possible to construct this same type of fencing across the border’s diverse terrain; the Department of Homeland Security (DHS) said it would be impossible. So, it was proposed to allow DHS to determine where it would make the most sense to build high-tech fencing, physical barriers, roads, lighting, cameras and sensors. This proposal passed in 2007, with a budget of $1.2 billion.

By 2011, DHS had reported building 350 miles of fencing, costing approximately $6.5 million per mile and about 299 miles of vehicle barriers, priced at $1.7 million per mile. This resulted in scattered fencing, disconnected pieces and a lot of dollars spent along the southwest border. During the same year, the Obama administration cut funding for a “virtual wall” project that President Bush had initiated in 2005 to replace physical fencing with mobile surveillance and unmanned drones across the entire 2,000 mile border. However, after $1 billion was spent, only there was only 53 miles of virtual surveillance to show. Homeland Security Secretary Janet Napolitano found that this project didn’t meet “current standards for viability and cost effectiveness.”

Now on the scene is presidential candidate Donald Trump, who plans to use his negotiating skills to force Mexico to pay for the border wall. (I guess after spending billions on this “border wall” concept, we are a bit strapped for cash!)

And, so, after a merry-go-round of attempts, we are still left with the following question: Should the U.S. even build a fence along its borders?