Originally Posted by ask me anything
Don't forget Flash can vibrate through solid matter, so Minato couldn't physically touch him even if he wanted to.
In the case of the flash though he can't just do it instantly. It has to be a conscious decision on his part so its based mostly on reflex action when a threat is about to happen. If Minato some how managed to catch the flash completely off guard without any physical warning than he could potentially kill him. Then again a lot of shinobi in naruto could easily kill the flash if they caught him off guard. He isn't exactly what I would call the most resilient of heroes in the DC universe.