"what humanity really needs, at this critical stage of our evolution, is a colossal hypersonic cannon"
I wouldn't worry, this continues the trend to fewer and fewer unfeasibly expensive weapons. The procurement cuts to (say) the F22 programme show what happens. Originally USAF had a "kiddy in the sweetshop" procurement plan, that called for 750 jets, which was progressively cut back as costs rose, until only 188 were built, with cost per aircraft climbing from under $150m to over $400m. This unsustainable cost escalation and reduction in hardware has been seen in all services, in all Western countries, and as a result fewer weapons get bought, but governments still incur vast increases in public debt, and their capacity to indulge themselves in hobby wars decreases.
Our colonial cousins still have enough poke to keep interfering in foreigners affairs, but the UK, with it's twenty ship navy, seven combat squadron air force, and increasingly part time army show how this pans out. Our armed services could probably defend us against a Danish attack, for example, but we'd struggle with anybody bigger.
From a logical perspective if the politicians don't have the resources to fight anybody, then they won't be able to, but as we've seen time and again our leaders are more than happy to start purposeless wars which our military are ill equipped for. Luckily we don't have a Nimrod fleet any more, so we won't be embarassed by Russian submarines in our territorial waters as we won't know they're there.
So, pacifists everywhere should be supporting rail gun development, exo-skeletons, laser cannons and all the other madcap ideas of military suppliers as the best hope for global peace.