First of all, ISIS isn't a country. They are an insurgency. They have no formal alliance. They have no army to call upon. They are terrorists. Nearly everyone in the world is against them.
Second, this shit has been going on for decades. We are just more aware of it now because of global coverage. I mean, look at all the major IRA attacks during the 80's and 90's. How many of them can you name personally?
Third, wars aren't fought like that anymore. People are so interdependent on each other, not only to trade resources but also on each other's production. Countries are so specialized that it is pretty much impossible to outright declare war. Instead, there is cyber-warfare and small scale wars fought in third world countries where enemies back rival factions discretely.
Don't buy into media fear monger bullshit.
While I agree, its worth noting that similar things were said about national interdependence before WW1.
I understand that, but there is a huge difference; in WWII they were looking at trading raw resources. Nowadays, countries benefit from specialized (and often less protected) wokers. Whereas a country could simply invade territory that contained valuable resources (such as Japan's invasion of the Dutch East Indies for thier oil reserves), nowadays though, things are a lot more complex.