Republican Sen. John Cornyn (Texas) is raising concerns about the Trump administration's construction of a border wall through national and state parks in his state, saying the concerns come from his constituents that the Trump administration should meet with. The letter comes after Cornyn lost a GOP primary to Texas state Attorney General Ken Paxton, who Trump supported. Cornyn's letter about the parks arrives at the start of wall construction at the national park, which is located on the bend of the Rio Grande. Earlier this year, then-Homeland Security Secretary Kristi Noem waived several environmental laws as part of a bid to speed up border wall construction in the region. The border wall has been a particular political priority of the president's, particularly during his first term in office.