“The reason that U.S.-trained foreign forces usually do not prevail is not because they are poorly trained and ill-equipped. In fact, they often have better equipment and far more extensive training than their opposition.
Yet they repeatedly fail largely because they are not as motivated. Military success on the battlefield is more dependent on whether men and women are willing to fight and die for a government they believe in. Rather than how well trained they are, troops have to believe their government is acting in the best interests of all its citizens.”
This article does a nice job of identifying a clear historical pattern by linking the failures of US policy in Iraq and Syria to similar failures in Afghanistan and Vietnam. I am not 100% convinced by the “lack of motivation” argument, which has become the standard explanation for the problem. While it is likely part of the story, perhaps there is more of a mid-level explanation. Rather then it simply being a either a failure in US training or a question of troop motivation, in some cases I wonder if there are also issues with leadership (i.e. the officer corps rather than the troops), command/control and organization, and battlefield tactics.