Cookouts, fireworks and the "1812 Overture." On the Fourth of July, we hold these truths to be self-evidently American, right? Don't light the cannon fuses just yet. The "1812 Overture" may be an American tradition, with its patriotic strains and thunderous battery. But while orchestras across the land, including the Pittsburgh Symphony Orchestra tonight at Point State Park, will perform it with clanging bells and cannon fire, the music could hardly be any more distant from the Stars and Stripes. That's because the overture, written by famed composer Peter Ilyich Tchaikovsky, depicts Napoleon's retreat from Russia in 1812, not America's...