He's mostly correct. But I wouldn't say we have zero interest in Africa. Hearts and minds do matter but won't be gained at the end of a rifle barrel. Then there is the cold war chessboard theories of blocking access to your rivals being 'good for the national interest' but that is debatable.
I think he’s 100% right, given our recent history.
In theory, it is true that our security will, under certain circumstances, justify our involvement in foreign conflicts.
But in order to distinguish whether those circumstances exist in a given case, and justify an action, there would need to have been pre-established policy, and a long record of strict and consistent application of those policies.
That has not been the case since WWII. We get tangled up in one mess after another.
We have become far too eager to get involved and meddle in other people’s conflicts. Instead, we should be extremely reluctant, so that the burden of proof rests squarely on the shoulders of those who would get us involved.