The difference between soldiers and (almost) everyone else is that the soldiers' job involves risking one's life.

According to the 2010 National Census of Fatal Occupational Injuries, the jobs with the highest fatal injury rate per 100,000 full-time equivalent (FTE) workers in the U.S. were:

• Fishers and related fishing workers
• Logging workers
• Aircraft pilots and flight engineers
• Farmers and ranchers
• Mining machine operators

The fatal injury rate for people in the fishing trade is 116 per 100,000 — or slightly more than 1 in 1000, per year. (If you value your life, do not go into the fishing business; and if you value other people's lives, you might consider buying farmed rather than wild-caught fish!)

According to this Congressional Research Service report, the worst year for U.S. military deaths recently was 2007, when 1953 out of 1.6 million military FTEs died. However, 235 of these deaths were due to illness rather than injury, whereas the above figures for other occupations deal only with injury. Subtracting these, members of the military are risking their lives slightly less than the people who bring you your salmon and tuna.

If you want to make a moral difference between soldiers and other people in dangerous occupations, you might consider making it on the basis that soldiers have to deal with threats to their lives that are caused by other people's deliberate hostile action. Humans tend to reckon risks caused by other people's deliberate action as being morally worse than risks caused by dangerous environments. Whether this difference should be considered a bias, or part of our utility function, or both, is another issue ...