Final answer:
Rome's war with the Seleucid Kingdom changed the attitude of the Roman Senate regarding expansion into the eastern Mediterranean after the Second Punic War.
Step-by-step explanation:
After the Second Punic War, the Roman Senate was initially opposed to expanding into the eastern Mediterranean. However, Rome's war with the Seleucid Kingdom changed their attitude. The Seleucid Kingdom, led by Antiochus III, sought to conquer and control the Greek poleis in the eastern Mediterranean. Rome feared that this would threaten their interests and Italy, similar to the threat posed by Macedonian King Philip V during the Second Punic War. As a result, an expansionist faction in the Roman Senate successfully convinced the Centuriate Assembly to declare war against the Seleucid Kingdom. Although Rome initially only aimed to defend Greek independence, their continued conflict with the Seleucids ultimately led to a shift in Roman policy towards expansion in the eastern Mediterranean.