According to Thucydides, the members of the league were partly to blame for their situation. They could not leave the league because Athens would attack. Athens was able to attack because the members had given Athens money to build a navy, instead of building their own. Was Athens justified in using the resources of the league in this way? Why or why not?

According to Thucydides history, Athens was not justified to use the resources of the league in that way.

Reason because Athens forced the league to continue paying, and used the money to build its navy.

Explanation:

Thucydides account of Peloponnesian war (431 - 404BC) described how the Delian League navy crushed the Persian navy. Some of the Delian league members thought the threat by Persia was gone, and the league was no longer necessary. Some of the islands in the Aegean wanted to leave the league, they no longer wanted to pay money and provide ships. Athens stepped in and did not permit these Greeks to leave the league. Athens treated these city-states harshly by tearing down their walls, taking their fleet of ships, and insisting they continue to pay the league taxes. Apparently It was easy to join the Delian League, but impossible to back out, and the league was beginning to look more like an Athenian empire. Athens forced the league to pay, but used the money to build a navy and becoming hostile to the league.

Athens was not justified in using the money and resources of the league to build its navy and attack other city-states; the reason why Athens was not justified was because it (Athens) was also a member of the body of Greek city-states-known as the Delian League-which had a lot of successes over the Persians. On the other hand, the members of the league can be blamed for their situation because they opted to leave the Delian League which was powerful because of the navy that was controlled by Athens; the decision of the city-states to leave the League, prompted Athens to forcefully subdue and control the city-states/members of the League.