Today's neo-isolationists (or "non-interventionists," to use their preferred euphemism) seem oblivious to the need for a strong American presence around the world. (The promiscuous use of the term, "world's policeman," is intended, evidently, to promulgate a sense of disdain in others.) And this is true of both the libertarian right (which views America as too good to be sullied by the rest of the world) and the traditional left (which views America as morally suspect, and therefore likely to contaminate the rest of the world in the course of its interactions with it).
Here is a bit from an article on the subject by Michael Goodwin (who focuses upon President Obama, and his own form of neo-isolationism):
The world looks to America, and America looks away. “It it is time to focus on nation-building here at home,” [President Obama] declared, as though the Earth would take care of itself in a one-big-happy-family kind of way.
It turns out that the committee system is no better at running the global order than it is at running a corner grocery.
Somebody has to take the lead and assume responsibility for success. Somebody has to set the rules and enforce them.
That somebody used to be America, and it is no accident that when America led, the Earth became a better place for more people. The seven decades after World War II marked a historic era of peace and stability around the globe.
As Robert Kagan wrote in “The World America Made,” his 2012 book, “The most important features of today’s world — the great spread of democracy, the prosperity, the prolonged great-power peace — have depended directly and indirectly on power and influence exercised by the United States.”
And the link to the entire article: http://nypost.com/2014/03/19/beaten-obama-turns-his-back-on-the-world/