States do not merely defend the power they have: they seize every opportunity to gain more that looks cheap and likely to succeed.

I'm not a defensive realist, I'm an offensive realist. And my argument is that states look for opportunities to gain more power, and every time they see, or almost every time they see an opportunity to gain more power, and they think the likelihood of success is high and the cost will not be great, they'll jump at that opportunity.