You are right in tha aspect that terrorism doesn't care about excuses (at least externally, it needs to justify its actions to its "follower base" though).

I have an intuition that the grandparent tried to express someting like:

Now Hezbollah has a motivation to attack Hungarian interest in the EU.

Which I'd simplify as something more concerning for me, as a Hungarian: Now Hazbollah has motivation to attack Hungarians.