As he promised during the election campaign, Trump is determined to build his "big beautiful wall". While this shows that he keeps his promises, I think this wall can only bring bad things in both cultural and economic sphere.
In the economic one, since the construction of the wall will cost bilions of dollars, American citizens will have to pay taxes to finance such a huge project. Also, there is no reason to finance this project because Mexican illegal goods cross the American boards through legal customs, so things won't change. Trump will have to find another way to solve this problem without spending so many dollars on a useless and bulky wall.
In the cultural sphere there have already been famous cases of walls, for example the Berlin Wall, that caused several problems and division between the people. Those barriers weren't only material but also mental and invisible ones. Walls have always divided people and nowdays there should not be such a cultural hedge. There are already barriers of all types everywhere and in every context, we are fighting to destroy them because still today people are judged by gender, race, religion and sexual orientation. This is wrong. We have to stop it and throw down all kinds of walls, we are all human and we have to be respectful of each other just the way we are.
This is why I say "No more walls".