The 250th anniversary of American independence is colliding with political polarization and a heat wave as celebrations get underway across the United States on Saturday. President Donald Trump plans to speak on the National Mall in Washington ahead of a massive fireworks show. Elsewhere, fireworks are scheduled in Chicago and New York City. In Los Angeles, Queen Latifah will host a concert featuring The Smashing Pumpkins and Chris Stapleton. The East Coast faces intense heat, causing some events to adjust or cancel. Meanwhile, the Pacific Northwest enjoys milder weather. Celebrations unfold amid a deep political divide in the United States.