The French probably would have joined the British side too who at the time had the largest and 'most powerful' army at the time.

:EDIT:

Germany possibly could have joined the side of Britain too as America has vast lands that Germany could have used for its 'breathing room'.

It's highly likely Germany would've allied with Britain.



Not to mention, with free reign over Europe, Germanys industry wouldve bloomed & America would find herself being dominated at sea by the Royal Navy & a much strengthened Kriegsmarine while the RAF & Luftwaffe destroyed your cities from bases in Canada & South America.

*EDIT*

And let's not forget Japan.

You just plan wouldn't have beaten Japan with Britain as her ally.

you realize that the US supplied a large portion of all allied nations in some way shape or form the USSR was supplied the most under the lend lease agreement then it would have been the UK because they couldn't produce stuff in the numbers the US could due to raw material and there empire was spralwed out meaning stuff coudl be intercepted just as well and the us produced more ships then any other in ww2 for both them selfs and the UK as well, Attacker class CVE any one.

So as trying to say the UK wouldn't have lost hands down no contest kind of thing i am not but i will not say they wuold win uncontested either because when it comes to it the US out produced all allied nations combined pretty much. and I'm not saying the Us would have won either hands down it would have had a hard time but it could very well win if it gots its building speed up wich every one knows it would have .

For the thing wtih japan jioning them they hated the brits for restrianing there navy interms of capital ships.

once i find my book about the lend lease agreement ill list the total tonnage of stuff give to each nation if any one wants the stats and what each thing was with its own tonnage,

Britain could easily conquer 30s Europe and eclipse Americas potential Industry

@kos123

You are also forgetting that Americas manufacturing prowess was never affected by bombing, naval firepower or ground offensives. Forces could easily push into Northern US states from Canada over their vast border, as well as air strikes from Canadian airbases and British an French carrier forces.

Think of how flat New York and Washington would have been if they faced naval bombardment from the British (and French navy since they would most likely join the British side). Production rates would equal and if not surpass American production in France, Britain, Canada and Australia.

By the way, the Russians out produced America (with the exception of naval production) and the amount of resources sent to Russia was scarce, as well as greeted with disappointment by the Russians as their own materials were superior to what was sent (KV equaled the Churchills that were sent by Britain and T34s far outmatched what small numbers of Shermans were sent).

dispite the plan being a land war, the key would have been sea power in the long run, IF Britian could hold a large port on the Canada atlantic coast with its based in Jamica and Barbados it could have enforced a sea blockade. if it lost all port access in the north then it would have been harder to enforce and there would have been more holes for blockade runners to slip through.

i personally doubt that germany would be pro active in the help for the british empire but they may have stopped all trade with the US and suppoted Britian with intel and at cost supplies.

as for the French, well they may have gotten involved if they could get a quid pro quo, i guess something like the french part of canada back, but without that they would have sat on the side lines wating to see which way the cards fell.

you may also have found that troops would have moved from the ANZAC and India whith the support of the British Pacific fleet to either invade Hawai or Alaska or to the Panamar cannal to cut off shipping from Atlantic to Pacific.

Remember folks this is lat 1920 and really early 1930 before Hitler even was with the power (he gain that power 1933)
1930 i dont think USA would have last on theirs borders very mutch but as more you go into USA the less space the US Army have to defend so they while get more power from that and while be harder to beat.
USA have proved that they wont back down if they are threated or attacked by anyone.
Btw 1930 the ground attack aircrafts was very very very very rare on Germany hade the knowledge enuf to earn on ground attack aircrafts or GAA.
The only thing actually the british empire would win on is theirs navy, since the army then was still with The Great War weapons.
So i think USA would have won the war then in the long run but they should have had big loses early in the war.