Waive the laws?

Let me see if I have this straight:

1. Congress passes laws that restrict land development
2. Congress passes laws calling for the building of a fence along the border
3. Congress passes laws saying that their restrictive land development laws can be waived so that the fence can be built more quickly
4. The Department of Homeland Security exercises the option referenced in #3 to waive the laws and go ahead with building the fence
5. Congressmen protest

It seems like Congress said that DHS could go thus far, but when they do go thus far, they don't like it.

I think I'll ascribe it to foolishness and leave it at that.