I mean, we are already taking aggressive action to cut off ISIS funds, the fact that it’s not 100% working shows it’s not simple. For starters even after you cut funding they continue to leach wealth out of the land they’ve occupied. Beyond that you can’t really shut the funding because in a lot of regions that’s paramount to shutting down the economy which just breeds more extremism. It’s hard to distinguish which is really which, it’s one big black market. If ISIS has the guns and taxes all of the local businesses (which they do) you’re basically saying we should cut off all sources of cash flow to the entire region and starve Syria out. Which A) requires a ground force (see Assad / Allepo) and B) is kind of the worst option from either an effectiveness or humanitarian standpoint as it C) also breeds more extremism and works against your books and education policy. It’s not like they just have ISIS, Inc signs up. Beyond that, countries like Turkey and their neighbors just continue to buy oil, etc off them anyways quietly. Then lastly, KSA and other organizations continue to slip money in though disguised means that we haven’t been able to fully identify. Without a ground presence it becomes even more difficult to execute or even distinguish because you’re trying to do all of this from 10,000 miles away. At the end of the day it’s just easier said than done, regarding fund cut offs.