Anyone who condones what happened is an asshat. However, anyone who thinks it was out of the blue is a dipshit. We've been meddling there for decades prior, we continued the British and French tradition of imperialism and destabalization, they'd been stepping up their attacks and repraisals.
Also, when this guy said and to paraphrase "the guy who took his eye is brave". He's not wrong. Whether it was in a firefight (more brave), or by digging a hole somewhere to plant an IED with death dealing remote controlled robots in the sky, or apaches, capable of using FLIR, or thermal optics to see your dumb ass in the middle of a road digging a hole with a 155mm artillery shell beside you, that's brave too, less brave than going tip to tip with a rifle, but still brave.
These guys are also not "terrorists". Attacking military targets is literally the opposite of terrorism. Now, it's true that some people involved in insurgency are also involved in terrorism, but not all insurgents in Iraq and Afghanistan were involved in terrorist activities. Bravery as a concept isn't attached to whether or not you agree with their motives or reasons for fighting. Bravery in this context is being willing to risk your life for some ideal you hold to be higher than your own, and to do so against overwhelming odds. Anyone who engages the US military, or coalition allies in a firefight, or by operating in the middle of the night to plant bombs knowing that any second a Predator could end their life before they know its coming, is brave.
There are a lot of ex-servicemen who fought the Taliban, and they will tell you, the Taliban were good, often better than coalition forces. The big difference was follow through, staying power, and the full spectrum support that coalition forces had from indirect and direct fire support.
But this is really two issues isn't it. The towers were attacked by Saudi Arabians, funded by Saudi Arabians, sponsored by Saudi Arabians, but not Saudi Arabia right? Right?! The Taliban and the various Sunni and Shia militias in that fought an insurgency against the US and coalition forces, were, when they were carrying out insurgency, not terrorists, and for facing down the worlds greatest military power with ancient rocket propelled grenades, rifles, and the odd mortar, pretty fucking brave.