"Neither conscience nor sanity itself suggests that the United States is, should or could be the global gendarme"

This quote by Robert McNamara recommends that the United States should not tackle the function of global cops. McNamara is indicating that it is neither morally appropriate nor useful for the United States to take on the obligation of policing the world. He is recommending that the United States must not be the one to impose global laws as well as regulations, as it is not their duty to do so. He is also indicating that the United States does not have the resources or capability to handle such a role. McNamara is recommending that the United States should focus on its own interior problems as well as not attempt to handle the function of worldwide authorities. He is highlighting that the United States should not be the one to determine the regulations and regulations of the globe, as it is not their place to do so.