Final answer:
The Supreme Court has recognized the Second Amendment as serving to restrict federal power and to protect an individual's right to have arms for lawful purposes such as self-defense. This protection is both a federal and state responsibility to uphold after the McDonald v. Chicago case.
Step-by-step explanation:
The Supreme Court's interpretation of the Second Amendment has evolved over time, with varying rulings indicating its purpose. Initially, in United States v. Cruikshank (1876), the Court suggested that the Amendment restricted federal power and acknowledged the pre-existing right to keep and bear arms. However, this interpretation shifted significantly with the landmark decision in District of Columbia v. Heller (2008), where the Supreme Court recognized the Amendment as protecting an individual's right to possess firearms for lawful purposes like self-defense in the home. This individual right was further cemented in the subsequent McDonald v. Chicago (2010) case, which incorporated this right against the states. Therefore, the purpose of the Second Amendment is seen as both limiting federal overreach and safeguarding individual rights to possess arms for lawful purposes, though the extent of regulation is subject to judicial review and not considered absolute.