How a White House plan to overturn a key EPA regulation threatens children’s health

In July, the Trump administration proposed revoking a landmark 2009 finding that’s been the basis for EPA regulation of greenhouse gas emissions under the Clean Air Act. If the proposal is finalized, experts warn that it could jeopardize the health of millions of Americans, especially children. John Yang speaks with pediatrician and clinical professor Dr. Debra Hendrickson for more.