Does the company have any due diligence to check if what they are doing has the appropriate legal approvals?
Who would they ask?
Did you show the electrician your deed when they worked on your wiring?
If a contract comes through 'official' channels, you assume it's official.
My contractor had to get a permit from the city before even modifying my kitchen, which included minor changes to electric outlets and plumbing.
I don't know what, if anything, "official" came down to these contractors, so we should find that out before we assume that there was anything official they received. Did they receive permission from the National Park Service? Did their work undergo National Historic Preservation Act (NHPA) Section 106 Review or National Environmental Policy Act (NEPA) Clearance?
Is it ok for them to cut the trees if they don't know they have to do those reviews or seek clearance? simply because they were told by the President to do so? I think a [reputable] contractor shouldn't "assume" things about their permissions to perform actions such as this.