When he invaded Poland he went to war with Britain. Conquering Poland didn't change that he was still at war with Britain.
No. Britain declared war on Germany two days after the invasion of Poland was launched. Germany has never ever declared war on Britain!
Hitler ignored a British ultimatum to give an assurance that German troops would withdraw at once from Poland, thinking they were not serious. Hitler could have complied, as there was from his point of view the possibility of restarting the invasion at a later date if the diplomatic position changes, without the British declaring war.
How could he just finish it in the summer of 1940? What navy was going to escort his invasion fleet? He had about 10 destroyers after the Norwegian campaign. To win he had to build the naval power to win which brings America into play. Also it leaves the Russians to keep readying their army for a war they start when they're ready.
Firstly by capturing most of the Allied forces at Dunkirk. Secondly by requiring the French, as part of the Armistice terms of June 1940 to place all French shipping and warships at Germanys' disposal. Thirdly by launching an all out attack on Fighter Command airfields in south east England and on the Chain Home radar installations within range of stukas, by early July. Fourthly by ordering a joint armed forces plan for an invasion of England along the Kent and Sussex coast, timed before the end of July to take the maximum advantage of the short nights before they start drawing in. Fifthly by destroying the RAF fighter forces by attrition by mid-July. Sixthly by getting Italian co-operation for an invasion of Britain, requiring as large a force of Italian torpedo bombers that can be assembled for Channel operations. Seventhly I would send the Scheer into the North Atlantic via the Denmark Strait, with orders to attack North Atlantic convoys. Eigth by invading Britain - it is only by the invasion itself that the RN is drawn into the English Channel where it can be targeted in daylight hours by the maximum Axis air strength. With the RAF now largely destroyed and the British Army still short of men, weapons and ammunition the main task for the Germans is securing the Channel crossings using air power as the primary weapon.
That is the winning strategy.
I'm afraid there's virtually no area where we would agree.
Firstly to capture the Allies at Dunkirk you'd first have to get rid of Hitler as it was his halt order that messed that up.
Second you can require whatever you like of the French but it doesn't mean they'll comply. The country might sign up but the crews might scuttle the ships or sail them away regardless. And how long would it take you to get them ready for German service if you got them? Months surely.
Thirdly if you go after fighter command in early July then yes they won't be as prepared as they were in early August but then neither is the Luftwaffe. The Germans also suffered heavy aircraft losses and aircrew exhaustion in the French campaign and would have found it just as tough to go straight into another fight as the RAF. In other words you'd have two airforces starting out both more depleted and probably with the same end result...stalemate.
Fourthly you can order the high command to plan an invasion for before the end of July but then they've got to russle up merchant shipping, Rhine barges which they have to modify as landing craft plus put together what few warships you have, all in a very short time. And with a high command who wouldn't even believe it would work anyway. Oh and who had zero experience at it.
Fifth I think the chance of wiping out fighter command by the end of July is nil. See thirdly for the reason why.
Sixthly do you think you could get the Italians to send their torpedoe bombers to northern France in such a short time? They'd be watching as well to see your battle with fighter command and if that wasn't working out I don't think they'd be to happy.
Seventh you could send the Scheer anywhere but if the Brits see you getting ready to invade they'll just be waiting for that with everything.
Eighth if you actually launched that invasion no matter how many ships they lost the Brits would destroy it.
We simply don't agree. But that's cool. Fascinating subject regardless.