^^^ Yes, walls exist. Why you think that has any bearing on the question confuses me.
Firstly, the fact that walls of different sizes exist in different countries at different points is largely irrelevant to the idea of a new, thousand-mile long wall along the Southern border.
I mean, the article you linked to has the following quote "Walls are public relations exercises where governments demonstrate that they are actually doing something," Vallet said. "They usually create more problems."
It isn't weird the Dems for not wanting to fund a PR exercise, but kind of gross that Trump would shut down the government over one.
But more importantly - what wall? Is it a physical barrier the whole length? If so how big and in what form? Is it some barriers some places but not everywhere? Is it reinforced building of what already exists? Is it new construction?
What?
Because Trump and the GOP keep changing what they say they are asking for whenever anyone tries to negotiate with them. It's a major problem and one of the reasons negotiations have stalled. As far as anyone can tell, he wants a blank check for... something. Because it is a PR exercise, he can't even come clean about what he wants. Laws kind of need to be specific. If he wants to build something specific, he has to say what he wants. You can't negotiate with someone who keeps contradicting himself. There is a reason people are joking about him changing his mind to a "beaded curtain".
Since you linked to the same story twice, I can only guess that you mean the Secure Fence act in 2006. Yes. No one has ever said there should be no barriers on the border anywhere at any time. Is Trump just saying he wants to reauthorize the Secure Fence act? Or reintrodcue the idea that it should have two layers of fencing? He explictly said on the campaign trail that law sucked because it wasn't a wall and it wasn't long enough. Has he changed his mind?
Remember, the Dems gave him 1.6 (or was it 1.3?) billion last year to spend on increased border security and reinforcing and expanding the existing fences and stuff. I don't think he even has spent much of it.