At least not on the basis of backward-looking statistics, assuming that inter-arrival times of major wars are correctly/most closely modeled by Poisson processe

At least not on the basis of backward-looking statistics, assuming that inter-arrival times of major wars are correctly/most closely modeled by Poisson processes as the authors believe. You could make a claim based on other things. For example, you could claim that the speed and fidelity of information transfer render it now more difficult to have a major war. You could argue that the incredible amount and speed of power projection we now have access to render international warfare game-theoretically very difficult. (For example, there will not likely ever be another amphibious invasion conflict between of equiv-tech major powers. There are too many weapons systems that can accurately destroy surface ships, so it would be impossible to get close enough to make landfall.) But any such claims could not be based on statistics.