To clarify, I was discussing the merits of buying a stack of 4 bombers and sending them to the Pacific.
Sure one bomber might get some targets to snipe at - but a full round buy doesn’t add much to what you already got with the starting bomber. Anything can be effective against an opponent making serious mistakes like leaving a transport stack naked and open to attack, and in a case like that, one bomber is as effective as four.
The issue is with the mechanics of movement over the oceans. A Japanese transport at a harbor can be in range to attack a bomber while the bomber is not in range to attack the transport, despite the vast difference in base movement - an airfield for the bomber makes no difference. Land units can effectively move 5 spaces to attack when using a transport at a harbor (one load, three move, one drop). The bomber would need 8 move total to attack that transport and return to base, and of course it only gets 7 with the airport and 6 without.
It’s totally counterintuitive when you look at base move 2 for ships and base move 6 for bombers, but in practice, that transport can attack from one space further away than the bomber can.