So now let’s ask, can it be done?
The best places to look for that answer is where others are attempting similar feats. Case in point, Saudi Arabia.
Along the Northern border of Saudi Arabia, bordering Iraq, the Saudis began plans to build a series of walls and fence works in 2006. Construction was expedited after the invasion of Iraq’s Al Anbar and Nineveh provinces in 2014 by Islamic State forces, where construction began around September of that year. The project calls for some 1000 km long stretch of varying degrees of fortified walls, fencing, and some areas manned with remotely operated UAV surveillance.
From the Independent Journal Review
“…consists of 78 monitoring towers, eight command centers, 10 mobile surveillance vehicles, 32 rapid-response centers, and three rapid intervention squads, all linked by a fiber-optic communications network.” 
Also is Israel’s southern border which, in the words of Israel’s Prime Minister, worked out pretty well.