I find it interesting that while scientists insist that we continue to pursue "pure research", there was a subtle shift in the 19th and early 20th centuries: before that, scientists were, functionally, hobbyists. That is, they pursued their interests either with the support of a wealthy friend (who generally had a vague interest in the subject, and/or found it socially advantageous to be seen to be a 'supporter' of scientist X) or at their own expense.
Because some governments saw a direct value into things like atomic research - and be absolutely clear, THAT was their motivation for funding such projects, not some high-minded devotion to 'pure research' - now it seems that scientists almost INSIST that research "should" be done on the public largesse.
I find that mind-shift curious and not entirely satisfactory.
Yes, to pry more secrets out of subatomic particles, we'll need to have bigger and bigger colliders. And to have the ability to drive from the US to Europe, we'd have to make a really expensive big bridge. Both could bring some sort of undefined benefit, but I'm not sure either is any more intrinsically justifiable (or silly) than the other.
Certainly in an era where governments are having trouble paying the bills, one would have to look carefully at such a project and say "well yeah, we *can* build it but not today". That, or accept that some of their spending priorities are out of whack and fix them FIRST, arguably a harder task than prying out deeper subatomic secrets.