cannot try dead people. Secondly, given that the terror group, Hezbollah, calls the shots in Lebanon, good luck trying to extradite those responsible. That is exactly why Israel, and other countries such as the USA, has to resort to extra judicial means to deal with those who seek to terrorize others.
Saudi FM: We hope Iran uses sanction relief for development, not nefarious activities (Reuters)
from the article: How a terror attack backfired on Hezbollah