Attack seeks defense: On the balance of offense and defense in security policy

About the article:

Offense has a bad reputation. Since defense has become the only legitimate goal of security policy, offense has largely disappeared from security policy parlance. Yet offense and defense are closely linked, and one is inconceivable without the other; not only because defense would not be necessary without offense, but also because pure defense is not possible, or at least not effective, without a certain offensive capability. But how much offense does defense need? How are defense and offense connected? And is it even possible to make a meaningful distinction between the two?