Except that ISIS didn't exist during the Bush Regime.
You're probably thinking of the Taliban or Al Queda. Both grew during the Bush years because he destabilized both Iraq and Afghanistan, while opening up Pakistan to trafficking.
Indeed AQ did grow early in the Bush years. By the time Obama became president, both support and growth for AQ was clearly on a downward trend. In fact, they had conceded Iraq altogether. Obama reversed this trend. No amount of pointing to Bush is going to change this fact.
ISIS (in Syria, should be a clue) is part or a larger thing which is Islamic terrorism. Islamic terrorism has grown every year since 2003. It grew because of what Bush did.
Just because ISIS has grown, which is mainly because they had a nice new battleground to play in. That doesn't mean that Bush was great and Obama is bad.
The Arab Spring created the vacuum in Syria combined with Obama supporting the ousting of Assad. The destabilization thereof gave ISIS fertile ground to grow. ISIS, in their former self, were just plain defeated in Iraq. Sorry, Bush may had created a mess but by the time Obama took the helm the folks we now call "ISIS" were clearly in regression. Obama reversed this trend.
Of course, it could just as easily be said that Islamic terrorism has been growing since the death of Mohammad. Which is, of course, why I give no credence to attempting to expand the argument in order to make a point not argued in the OP.