For everyone, particularly the entire population of Iraq itself. But the Pentagon has done a study of the effects of extended and repeated tours in Iraq. As reported in the LA Times for May 5th, their report "found that 28% of those involved in high levels of combat experienced acute stress, compared with 6% involved in low levels of combat." In addition, "the new report showed that 27% of soldiers who had been on multiple tours experienced mental health problems, compared with 17% who were serving in Iraq for the first time. I would say those numbers are low, but at least the effects of combat are being studied. This is in fact the fourth Pentagon survey of mental health since the Iraq war began four years ago.
PTSD might take forms other than stress - hostility towards others, for example. "Fewer than half of the service members questioned agreed with the statement 'All noncombatants should be treated with dignity and respect.' Forty-four percent of Marines and 41% of soldiers said torture should be allowed if it would save the life of a fellow service member."
To cheer yourself up, check out the daily coverage of the Phil Specter murder trial, or coverage of Paris Hilton being denied the glamour slammer and going to jail for 45 days for drunk driving.