Last week, Northrop Grumman (NYSE:NOC) announced a plan to buy back $5 billion worth of shares, hoping to retire 25% of its share count over the next two-and-a-half years. But why is Northrop buying back stock?

And should it be?

And can it afford to?

And can it afford not to?

Listen in as Fool contributor Rich Smith lays out the answers to these and other questions you may not even have thought of yet.