President Obama will headline the 20th annual Lake Tahoe Summit in Stateline on Aug. 31, the White House announced on Monday. Obama will headline the, which this year is hosted by Nevada Sen. Harry Reid. On Monday, White House Spokesman Eric Schultz said Obama will talk about how America can ensure that national treasures like Lake Tahoe can be protected for future generations. Celebrating its 20th year, the annual summit — the first edition of which was attended by then-President Bill Clinton and Vice President Al Gore in 1997 — has become an important yearly gathering of federal, state and...