When it comes to science in general, I’m a pessimist. I think we’re getting to the point of diminishing returns. But in this case, I’d say, do it- for this re

When it comes to science in general, I’m a pessimist. I think we’re getting to the point of diminishing returns. But in this case, I’d say, do it- for this reason: there won’t be any better time than now, because we have a whole scientific and engineering community with experience building these things. If we wait 30 years before we make the next one, all that experience will have to be rebuilt from scratch. It’s a false premise that technology always marches forward; expertise gradually gets lost and infrastructure degrades if it is not used. In a sense, if you’re not moving forward, then you’re moving backwards. If we don’t build this now, then in 30 years we will turn around and discover that we couldn’t do it if we wanted to. Plus, we might actually discover something useful!