Trust me, no one in their right ever decided to visit the Great Wall when it was being used for defense. not unless you wanted a face full of gunpowder and rocks.

Kuwait survived over 300 years thanks to its three walls. Each wall was built to meet the expanding population of the seaside city. In 1991, Kuwait built what was called as the country's 4th wall. It is very much similar to the Saudi wall you've talked about. The two additions it had, on the other side of the wall…

Now this is a wall

A construction project of this scale surely means well paying construction jobs for middle-class Saudi Arabians. Oh wait, sorry. This will surely be constructed using slave labor. Carry on.

It worked out for China for a very long time.

Two counterfactuals:

1. The Israeli wall worked. You can disagree with its existence, claim it causes untold suffering among the Palestinians and dislike it for a host of reasons (that I may agree with), but it stopped suicide bombings almost completely. Which is why it's immensely popular among the Israeli populace.

Actually, The great Wall worked really well for the Chinese for quite a long time. One could also argue, if you bu into the author of this article's premise, that it's still working admirably well. Consider the popular legend that it can be seen from space; what better symbol could you ask for?