Final answer:
The oligarchic rioters mutilated herms in Athens after deciding to invade Sicily, causing religious and political upheaval. The Athenians left the Acropolis in ruins as a war monument after defeating the Persians.
Step-by-step explanation:
The oligarchic rioters mentioned in the context of Athens after the decision to invade Sicily in 415 BCE engaged in acts of vandalism against the herms, which were religious markers or statues of the god Hermes placed throughout the city. Unfortunately, the materials provided do not directly reference the specific incident of defacement of the Hermes statues during that time. However, historical accounts from other sources describe that the herms were mutilated the night before the Athenian fleet set sail for Sicily, which led to political turmoil and accusations of religious impiety, greatly affecting the Athenian society.
Regarding the statues of Athena and what the Athenians decided after their city was looted and burnt by the Persians in 480 BCE, before the Battle of Plataea, the Athenians took an oath that if they were victorious, they would leave the destroyed Acropolis untouched as a monument to the war, which they did for thirty years.