President Trump had a broad strategic plan to control illegal immigration. The wall was just one part of that plan, albeit, the biggest and most visible.
There were probably 15 integrated elements to his plan and, taken together, they were very effective in controlling the illegal alien flow. They were going to become even more effective in the following years.
Then the Deep State installed Brandon who promptly destroyed every single element of the Trump plan.
Yep! Just think how many aliens in the US could be rounded up and expelled for $33 billion? For sure, it would be enough to complete Trump’s 738 miles of border wall.