Right now, we spend $3.8 - $4.2 billion on Border Agent salaries. That number is going to go up in the upcoming years.
A strong border wall would reduce the need to keep hiring agents along the border wall. It would allow them to deploy new technology like motion detection, drones and other forms of tech.
People who doubt the effectiveness of a new border wall are short sighted. They want to be pretend like they're progressives, but what they want is not change anything. The supporters of the wall are the real progressives in this matter.
Look at the cost of the annual budget related border security and immigration. $19.2 billion a year for 2016, probably well over $20 billion in 2018.
ICE accounts for over $6 billion annually. Instead of fixing the source of the problem, let's throw more money at border patrol and ICE instead. Those numbers will increase every year. In 10 years, the total annual budget can go as high as $30 billion.