America is too big for planes, too. If your transportation solution is flying, now everyone has to get around via endless highways or big, complicated regional airports, and you can only have so many of those. There's a reason why rural areas in North America have completely different politics from urban areas, and why so much of it is driven by a sense of isolation and abandonment. Trains promise to help here because they are able to stop in small places that will never, ever have practical airports.
A good rail network provides a reliable, consistent, repeatable, and straightforward three hour connection from Nowheresberg to the nearest city. Slow, but good enough to feel like they exist in the same planet. Unfortunately, that promise is subtle, and it plays out over decades, so the reward system we've created for ourselves is incapable of supporting it. And thus, we have Amtrak and confederate flags
USA: 9.53 Mio km² | 33.6 inhabitants per km² | $85,373 GDP (PPP) per capita | 32.5 Bn pkm (rail) | 1.98 Tn pkm (air, domestic + international (by departure)
Canada: 9.98 Mio km² | 4.2 inhabitants per km² | $60,495 GDP (PPP) per capita | 1.44 Bn pkm (rail) (2007) | 198 Bn pkm (air, domestic + international (by departure)
Australia: 7.69 Mio km² | 3.6 inhabitants per km² | $66,627 GDP (PPP) per capita | 10.5 Bn pkm (rail) | 220 Bn pkm (air, domestic + international (by departure)
India: 3.29 Mio km² | 426.7 inhabitants per km² | $10,123 GDP (PPP) per capita | 1,157 Bn pkm (rail) | 233 Bn pkm (air, domestic + international (by departure))
This quick comparison misses international inbound tourism, infrastructure size and infrastructure cost per capita as well as an actually spatially differentiated interurban density-adjusted connectivity parameter (or whatever that'd be called), so take it with a grain of salt, but I'd argue that while having different markets, those English-language adjacent countries have similarities and relevant differences.