Trumps wall will be defeated by the latest in secret technology developed by the cartels.
i think for Trump the wall is his sociopath ego run rampant. It is an extension for his tiny manhood that he believes will stand as some sort of monument to his greatness. In reality, if it even gets built in its entirety/partly, it will quite likely be torn down when the upkeep and maintenance costs prove pointless and there is a sane administration in the white house again.
The sad thing is he often refers to drugs pouring across the border as justification for it. The solution to drugs is legalizing them, this border will do nothing to stop the huge market for illegal drugs beyond perhaps raising prices. The cartels already use submarines, drones and all sorts of other methods. They're better funded than the Trump wall and will carry on as usual.