American forces in the Middle East are constantly under attack, but they aren't really retaliating. Here's why the US is holding its fire.

• Iran-backed groups have launched dozens of attacks on US forces in Iraq and Syria since October 17.
• The drone and rocket strikes have injured a number of troops, but there's been little retaliation.
• Middle East security experts say there are a number of reasons why the US is holding its fire.

US forces stationed in the Middle East have endured a constant stream of attacks from Iran-backed groups over the past few weeks, violence that's parallel to the Israel-Hamas war but nonetheless directly related to the bloody conflict.