Reason Three: We have spent a fortune in blood & treasure.
The Costs of War project says this regarding the human costs:
“At least 800,000 people have been killed by direct war violence in Iraq, Afghanistan, Syria, Yemen, and Pakistan. The number of people who have been wounded or have fallen ill as a result of the conflicts is far higher, as is the number of civilians who have died indirectly as a result of the destruction of hospitals and infrastructure and environmental contamination, among other war-related problems.
Thousands of United States service members have died in combat, as have thousands of civilian contractors. Many have died later on from injuries and illnesses sustained in the war zones. Hundreds of thousands of soldiers and contractors have been wounded and are living with disabilities and war-related illnesses. Allied security forces have also suffered significant casualties, as have opposition forces. However, the vast majority of people killed are civilians. More than 310,000 civilians have been killed in the fighting since 2001.”
A Costs of War report released in November 2018 included this:
“Nearly 7,000 United States soldiers and sailors have been killed post-9/11. But deaths do not tell the entire story. Since 2001, more than 53,700 U.S. soldiers and sailors have been officially listed as wounded in the major post-9/11 war zones wars. Many other U.S. soldiers have become amputees. From the start of the wars through mid 2015, there were 1,645 major limb amputations for U.S. service members associated with battle injuries in the major war zones.
The Congressional Research Service has stopped releasing regular updates on U.S. military casualty statistics. In its most recent report, issued in 2015, the Congressional Research Service found that more than 300,000 troops have suffered traumatic brain injuries.
Suicide is also an urgent and growing problem among the veterans of the post-9/11 wars. Although it is difficult to tell how many of these suicides are by post-9/11 war Veterans, because the VA does not disaggregate by war, there were more than 6,000 Veteran suicides each year from 2008-2016, a rate that is 1.5 times greater than that of the non-Veteran population.
Between 480,000 and 507,000 people have been killed in the United States’ post-9/11 wars in Iraq, Afghanistan, and Pakistan. This tally of the counts and estimates of direct deaths caused by war violence does not include the more than 500,000 deaths from the war in Syria, raging since 2011, which the U.S. joined in August 2014....The wars are ongoing, although the wars in Afghanistan, Pakistan and Iraq are less intense than in recent years. Still, the number of civilians killed in Afghanistan in 2018 is on track to be one of the highest death tolls in the war.”