Militarily, they are due to the insular geography around them that doesn't let them using their size to their advantage. In terms of manufacturing for nations that don't want to deal with E-waste, not so much. I'm not as convinced of the "collapsing" demographics relative to every other developed nation. While a contraction of 1 Billion people down to 900 million--let's make that 800 million--is a significant percentage of 20% loss, that's still a lot of people left over. If the US lost 200 million people from aging demographics, that's an extinction event. Therefore, we must conclude that low birthrates and aging population is a bigger issue for the US because our margin of tolerable losses is worse. We see the results in the West's permissive immigration policy trying to cover up this problem.
I guess OG Uncle Joe was right about manufacturing numbers too.