Pres. George W. Bush signed the Secure Fence Act of 2006 into law approving $50 billion for construction of hundreds of miles of fencing along our border with Mexico.  With bi-partisan, enthusiastic support, they said it would protect the American people, make our borders more secure, and was an important step toward immigration reform.  Schumer, Pelosi, Obama, Hillary, and Baucus voted for it.  Where is that money now?  All we know is that by the time Donald Trump was president (10 years later), no one seems to know the answer to that simple question.  Some work was done, but it’s not even close to $50 billion worth.
The drug-peddling, human trafficking cartels, as well as MS-13 gangs and terrorists, know exactly which parts of that border are the easiest to cross.  Throughout the Obama Administration, border control agents described their job as an unending battle of wits, a cat-mouse game with the constant threat of violence and endangerment to people.  Then, as now, they plead for a wall (or whatever Dems are calling it these days).  America grew-up with walls; they were called things like ramparts and forts.  So what changed?  Two things:  Trump is president and a 2011 study found that a wall would cause “fragmentation that adversely affects wildlife”.