But the veteran instructor at the military's explosive ordnance disposal school tells his young students to be confident in the chaos. Bombs hidden along the roadside and elsewhere remain the top threat to U.S. troops in Iraq and Afghanistan, accounting for about a third of all deaths, and it will be the trainees' job to defuse them.
"If something goes wrong and you pout or get upset and people see it, then they are going to be uncomfortable," Gura tells his students. "You are the calming influence."
That real world advice is more important than ever as the Armed Forces push to graduate more and younger bomb technicians, one of the most intense jobs in the military.
The Navy recently began allowing recruits to become bomb technicians as their initial job rather than requiring two years of service, a waiver that Army and Air Force already grant; Marines still have to serve two years before learning to defuse bombs.
Meanwhile, the Army wants to double the number of soldiers graduating the military's multibranch school for bomb technicians to 1,000 a year.
That all puts added pressure on war-weary bomb technicians like Gura, who has served three tours in Iraq, to perform overseas and share their knowledge back home.
"We are the busiest we've ever been - period, all four services. All of our instructors have done multiple deployments," said Lt. Patrick Gerhardstein, the school's training officer, who's missed three of his son's four birthdays because of military duties.
"The op tempo is going, going, going. We bring the veterans here because they have the knowledge of what's going on in theater. We also try to give them time to decompress."
Instructors say the loosened requirements let students learn the craft earlier, but sometimes those students lack the discipline that comes from serving two years in another Navy job. It falls to veteran instructors to teach the recruits the ins and outs of Navy life, Gura said.
For students, the school is a busy and competitive place - to gain admission, they must excel on aptitude tests and meet stringent physical standards. Dozens of soldiers, Marines, airmen and sailors attend classes together, spending a year learning how to disarm land mines, unexploded rockets, IEDs and other explosives. About a third don't graduate, but about 1,000 a year do.