Yeah, Japan didn't really give enough credence to the size of our Navy or our willingness to just dominate the Pacific ocean the hard way.
Had Japan pressed the attack home on Hawaii they would have won. And with Hawaii down we would have basically no ability to project power in the Pacific. Fleets can't operate too far from friendly ports--and we have none between the US and Hawaii. Retaking Hawaii would have been nearly impossible and we would have been basically powerless in the Pacific.
The US Navy could have island hopped Northwards from Australia, rather than Westwards from Hawaii. General MacArthur had his base in Brisbane for two and a half years between 1942 and 1944.
One benefit of fighting a World War is that you have allies in convenient places, that you can rely on to let you use their port facilities.
It wouldn't have been as easy to get materiel from CONUS to the staging point(s), but then, it's not exactly
easy to get materiel from CONUS to Hawaii, much less Guam or Iwo Jima. I reckon the US Navy could have done it, handily enough. Probably would have taken longer, but then, Japan was going backwards wrt ships and materiel from 1943 onwards, while the US was outproducing the rest of the world.