BAGHDAD, July 4 — At about 1800, we leave the horrors of the hospital and head to the embassy compound to sample some of the day’s festivities. Next to a huge, weirdly shaped lap pool, a classic-rock band is warming up. There’s a dunk tank, with good-natured soldiers taking the plunge, and lots of tables and booths set up. Around one of them, a group of black, white and Hispanic men of all sizes and ages push the caramel and candy apples. The Crossed Swords Mason Lodge of Baghdad raises money for their favorite charity—a prosthetic clinic for Iraqis.

Around 2000, Lt. Col. Clayton Simon, the sole pathologist in Iraq who earlier walked me through his FBI-like work, now takes me to the roof made famous by HBO’s "Baghdad ER" The talk up here ranges from family to war, honor, loss and a good smoke. Capt. Christopher Baugh, an ER nurse, walks over smoking a cigar, and Simon asks to join. “Do you have a small one?” he asks. “I got to get that smell out of my nose.”

We sit for a while, sometimes talking. Not-so-distant booms put us on edge, but not enough to make us leave. As choppers come and go, shuttling the wounded to other hospitals, their flares flame green and yellow against the dusty black sky. Suddenly, to the south, a plume of white and green: This time it’s not chopper flares, but fireworks. Happy Fourth of July. —Leslie Sabbagh