Wait, are we still talking economic metrics here? Because if we're not
as ISIS isn't listed on the stock exchange & your considerations on its
birth being wrong ( it having spawned in Irak out of the 2003+ mess
from an Al-Qaida chrysalis ) then we're left with European politics/cies.
Europe cannot really split ( although it could explode ). If it had had to,
the Grexit thing and 'em loner lads cry-babying would have done it. Now,
I don't know what you've been told but here's how it goes from the inside :
Europe is founded on the Franco-German couple. That explains most of its strength and most of its quirks.
It is then trying to include a big exception, the U.K. and many small ones, expl. rest of both of the above.
Thus the Brexit thing ( UK referendum to leave the Union ) is bigger than say Hungary, the most fragile of
the last round of members, getting out due to ISIS pressure ( as in refugees for example ).
One of the frailties of Europe is in its unified defence that shines by absentia. But that is more of a strategy
for politicians and "geo-politicians" to further because there are multiple solutions in the meanwhile. NATO
links most partners as Ireland, Sweden, Austria, Finland and recently Malta are associated through its PfP.
Cyprus remains apart but that won't break Europe, whatever happens.
At the same time, there is a clear defence pack between France and Germany. There is a clear offensive
pact between France and the UK. There are regular exercises being held between the remaining members.
So unity, maybe not but strength? Hell yeah!
The only thing that could help the validity of your claim would be a political
crisis due to social stress from either the refugee flow or the terrorist attacks.
And on that level, I fear the politicians as Europe's nemesis more than the will of the Peoples.
So it could happen that way due to ISIS but then again, it could happen that way too due to ...
increased ice cream taxation somewhere or Brussels & Strasbourg lowering further their efficiency.
The latter looks the most promising IMHoO
Have a great day, Tay.