Everything You Always Hated In X-Men
6. Why Didn't Xavier Make Sabretooth Remove Magneto's Helmet?
At the end of the film's second act, Magneto takes custody of Rogue, and Professor X uses his abilities to mentally possess Sabretooth, in turn grabbing Magneto by the neck in an attempt to stop him.
However, Magneto uses his abilities to turn all of the surrounding police officers' guns around on themselves, and then threatens to fire them if Xavier doesn't let Sabretooth go.
Xavier relents and in turn proves himself to be considerably stupider than anyone expected. Namely, why didn't he just have Sabretooth remove Magneto's helmet, which would've allowed Xavier to control and subdue Magneto also?
Yes, the answer is basically "because movie," but it's still a glaring oversight that Xavier of all people would miss a wide open opportunity like this.