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The impact of the US death toll on military families
Since the US military toppled Saddam Hussein, Iraq's former president, it has faced a violent anti-occupation campaign and witnessed violence between the country's sectarian communities.
More than 80 per cent of soldiers killed have died in attacks by al-Qaeda in Iraq, Sunni and Shia fighters, icasualties.org said.
The remainder died in non-combat related incidents.
Around 40 per cent of those killed were struck by roadside bombs, according to the website, making these weapons the main cause of fatalities.Small-arms fire was the second biggest killer, the website said, with helicopter crashes, ambushes, rocket attacks and suicide bombings also the cause of many deaths.
Vietnam was the deadliest war for the US military, apart from the two world wars, with 58,000 soldiers killed between 1964 and 1973, an average of 26 a day.
On average, just over two US soldiers die each day in Iraq.