Little Hungary managed to build a fence along its border with Serbia very rapidly, using soldiers and prisoners. Israel of course has a security fence to protect themselves from Muslim terrorists. So a fence sounds feasible to me. I just hope it is not some massive federal contractor project - instead we should deploy the Army Corps of Engineers and just build the thing working around the clock, similar to how the highway to Alaska was built during the Big One.
“I just hope it is not some massive federal contractor project ...”
If it’s handled as incompetently as healthcare.gov, it will cost 100s of billions and fall down the first day.
Actually the environmental impact study will take 5 years at least.