> and the undersea cables (more inhospitable than the remote desert) are far, far higher bandwidth

Terrestrial cables are likely harder to lay: you have to worry about land access—national parks, native title, private land—and the W.A. outback is an extremely challenging environment to work in.

Getting dedicated DWDM fibre to Murchinson is a big project unto itself.

The optical private network from CERN to the tier 1 site where I work was upgraded from 10 Gb to 40 Gb between the first and second runs of the LHC. depending on what goes on during the second run that might need to be increased again. Building high bandwidth infrastructure for use by lots of (paying!) customers is probably more viable for large corporations than it is for science, where you have a budget at the start rather than having things pay for themselves over time

The storage will need to constantly increase in that time, too.

Yes, of course, but this seems to be a problem where the solution is easily costed, is commercially available etc, whereas I'd imagine that the rest of the project is filled with a whole load of world-firsts.

Tier 1 = fermilab?

The NSA can do it, maybe they should contribute some engineering effort to help scientific causes like this and gain some good PR in the process.