U.S. historic preservation law faces the most serious threat in its 60-year history

Historic preservation advocates say the Grand Canyon and Arlington Memorial Bridge — where President Trump wants to build a 250-foot arch — are examples of historic sites that would lose protection under the proposed changes.

Congress and a federal agency are threatening to weaken the country’s historic preservation law, fueling a backlash that critics say is as fiery as the one that led to the law’s creation 60 years ago.