Would a wall be effective in preventing illegal immigration from Mexico to the US.?

The President Donald Trump decided not only to 'build a wall' to seal the southern U.S. border, but want Mexico to pay for it, at a cost of some $10 billion to $38 billion.

Whereas, Mexico reiterated it's refusal to pay the bill. This is a fact that a wall helps to a limited extent, as it’s limited at best, impractical at worst, and very expensive.

The best thing is that,with a market based visa system, Donald Trump can physically end illegal immigration within a month or two, even without a wall. And, staffing solutions and technological innovations can actually work for US Customs and Border Protection.

So, A Wall is not a solution to securing the southwest border, or any border for that matter.