This is not at all a pointless effort. First and foremost to legally recognize North Korean guilt, and secondly to delegitimize the "DPRK" regime. In their efforts to gain legitimacy, make it another obstacle the must resolve before moving ahead to achieve their diplomatic goals.
Key U.S. House Democrat cites troublesome issues in Iran nuclear deal (Reuters)
from the article: Israeli rights group sues North Korea over 1972 terror attack