Final answer:
The scenario where a defense contractor's top officer joins the Pentagon or a former Pentagon official becomes a lobbyist for a defense contractor illustrates the 'revolving door' in politics, highlighting the movement between government and private sector roles.
Step-by-step explanation:
Both scenarios described in the question, where a top officer from Lockheed Martin is nominated for a position in the Pentagon, or a former Pentagon official becomes a lobbyist for Lockheed Martin, illustrate the "revolving door" phenomenon in politics. This term refers to the movement of personnel between roles as legislators and regulators and the industries affected by the legislation and regulation. Revolving door laws are intended to prevent conflicts of interest by implementing a 'cooling-off' period, restricting recently departed members of Congress and other government officials from immediately joining the lobbying industry. However, despite these regulations, many former lawmakers still become lobbyists, navigating ethical boundaries and leveraging their insider knowledge and connections for the benefit of private interests such as defense contractors.