The wall is there to assist agents in securing the border. It’s one tool out of many agents use. When used properly it’s a huge asset. btw, there is no such thing a s completely fail safe system. But when used properly a wall can drastically reduce the amount of numbers coming into the country illegally.Walls can be breached. It's not a fail safe system. Ask the Chinese , their Great Wall worked until it didn't and that was huge.
Biden 2.3 million annually
Trump 400K annually
Pretty obvious who used the wall to his advantage and who opened the border.