how was hitler able to defeat france so easily in 1940?

The defeat of France was the product of a number of factors. Among them:

1. Germany had a much larger air force and so was able to achieve total air superiority

2. While France had a lot of troops and tanks, way too many of the French tanks were relics of world war I and used in combat against other tanks, and their lower population mean that they were a lot picky about their troops. They basically drafted every man who could hold a gun and having had less time to prepare their forces were mostly undertrained.

3. French and British morale was in the toilet while the Germans were flying high after their easy victories in the east.

4. Nobody had any experience with real tank warfare so both sides were guessing at how to use them. The German military guessed right while the French military guessed wrong.

As for the air war:

1. While the British had a smaller airforce, they could replace their losses much more easily because shot down pilot scould parachute back to their own territory, while German pilots shot down over England were lost forever.

2. The range of German bombers couldn't even reach deeper than half way into England, leaving large areas of it untouchable.

3. The Germans failed to realize that to disable the radar early warning system it wasn't enough to bomb the radar stations which could quickly be rebuilt. They needed to concentrate on the power lines and plants which supplied power to the radar.

4. The luftwaffe was factionalized and failed to stick to a single strategy.

5. The Luftwaffe was under-equipped with the heavy bombers needed for a strategic bombing campaign. Instead their force makeup was aimed at supporting tank advances with air power.

As for the invasion of Russia:

1. Hitler always intended to eliminate Russia because Russia was the biggest and closest threat, and run by Communists, who Hitler regarded as arch-enemies of his vision of the state. It was only a question of in what order he would invade them.

2. Hitler believed that Germany should conquer all of the resources it required rather than trading for them. Germany required petroleum. Russia had petroleum.

3. Hitler strongly suspected that if he didn't backstab Stalin first, Stalin would take advantage and backstab Hitler. The nonaggression pact was a purely temporary measure for Germany, a gamble that the Russians would hold off long enough for Germany to defeat its western foes.

4. The failure to secure air superiority over Britain meant the plan to invade Britain had to be canceled, so what else was Hitler going to do? Not invade something? That's just crazy talk.

5. The invasion failed because Russia is so insanely big it's like a snake trying to swallow a water buffalo to occupy it all, Stalin was a vicious maniac who would never give up or let his subjects give up, and because the Germans were ideologically driven to crush the "slavs" instead of doing something sane like proving to them that they would be a better choice than Stalin to run things.

It was a combination of factors.

One thing that's very overplayed is the Maginot Line; the line of fortifications that France built along its border with Germany. In the popular imagination people often say that the French sat behind the Maginot Line and the Germans went around it through Belgium, but that's just completely false. The French in fact built the Maginot Line to force the Germans to go through Belgium. The French sent their best forces and tanks to Belgium when the Germans attacked.

But what happened is that the Germans took a big gamble that paid off. Belgium can be roughly divided into two parts:

The northern plains, where most of the people live. Good roads, good tank country.

The Ardennes forest, which is less populated. It's not just a forest—it's also got tons of hills and cliffs. Poor roads.

So the French assumed that the Germans would attack through the northern plains. It was the sensible thing to do—the French knew that the Germans were very good at tank warfare, and it made sense for the Germans to attack on good tank terrain. Also, a German army officer carrying the original German attack plans—through northern Belgium—had to do an emergency landing in Belgium, and the Belgians managed to get a hold of these plans and send them over to the French.

The Germans in the end decided to send their main attack through the Ardennes; to fool the French, however, they started by attacking northern Belgium to make it look like it was their main attack. The French didn't figure out the trick, so they sent their best forces to meet the fake German attack; in the meantime the best of the German forces went through the Ardennes mostly unopposed and ended up attacking the worst of the French forces, the ones defending the sector that the French assumed was the safest.

That part of the explanation is called strategic surprise; the Germans managed to fool the French about their plans, and the French Army's best forces just ended up in the wrong place. A powerful army is no good if it's in the wrong place at the wrong time.

But what most people don't understand is that if the French had figured out the Ardennes trick in time, the Germans would have looked like total morons. The Germans' Ardennes move, for example, caused the worst traffic jam that the world had ever seen up to that point. Most German officers hated the plan. Hitler did like it; Halder (the military boss at the time, who'd been plotting against Hitler) thought privately that the attack on France was stupid, and that he'd rather pursue a plan that meant either quick success or quick defeat, instead of the northern plan which would mean a long war that he thought the Germans would lose at enormous cost.

Strategic surprise isn't the whole story, however. People often say that the French were trying to fight World War I again. Both sides knew that the war was going to be different than WWI: tanks and airplanes. But for the most part the officers in neither side knew exactly how it would be different. However, the German Army's training was better suited for these new situations. German training emphasized improvisation and initiative, while French training emphasized following orders.

So the Battle of France was a bunch of unexpected situations for both sides; the thing is that the Germans were able to improvise, while the French basically became paralyzed and unable to counterattack effectively once their grand plan to stop the Germans in northern Belgium was shown to be less than relevant. (Paralysis actually also happened to the Germans briefly; at one point one general managed to convince Hitler that the army was advancing too fast, and Hitler ordered them to stop for a day or so. Without this pause, the British might have never escaped from the battle.)

The French also had the problem that they had to coordinate with the British and the Belgians. Bad communication prevented some counterattack plans that might have saved France.

Another one: the French had more powerful tanks, but the Germans knew how to use their tanks better. One big aspect of this is that nearly all German tanks had radios, but the French didn't.

Yet another one: the Germans had better close air support. German army officers could much more easily radio in requests for bombers to come and strike targets of their choice. The French held a lot of their air force in reserve for the fight, while the Germans went all out with theirs. If the French had figured out the German plan in time back in 1940, the Germans would have looked stupid; instead of talking about the Germans brilliant and superior plan, we would be talking about how stupid they were to pick the worst possible sector to send their tanks.

And this is a realistic scenarion. The French had data that pointed to the Germans' Ardennes plan. They had warnings from diplomats in Switzerland and Belgium about German plans for the Ardennes and the Germans concentrating their forces to attack the Ardennes. They had flight data that showed the Germans concentrating their spy plane flights over the Ardennes. But Gamelin interpreted this as a German misinformation campaign—he judged that the Ardennes stuff was a ploy to distract the French from the northern attack, when in fact the northern attack was a ploy to distract the French from the Ardennes attack.

His blitzkrieg tactic worked really well and France didn't want to destroy their precious cities and artifacts, so they surrendered.

The air war against Britain was a failure, because Britain didn't budge and lasted through all the bombings without going crazy,

Hitler invaded Russia because he wanted european domination and Russia was a big part of Europe. plus he hated the communists.

Russian invasion failed, because hitler split the war into two fronts by invading Russia and the Russian Winter killed the German offensive, not to mention that the Russians burned every village they they retreated from, so that the Germans would have no food or supplies, and in the cold winter the Germans were starving and freezing to death.

It could have succeeded but it wouldn't have as Stalin would not let Hitler beat him until every soldier in Russia was dead.

You must remember that France had sustained massive losses in WWI and like many other countries was in no hurry to repeat the experience. Its generals were, as generals are always supposed to be, re-fighting the last war, preparing for a stalemate 'siege-style' trench war. In fact Hitler's younger generals such as Guderian had read with interest the inter-war military theories of Capt Basil Liddell-Hart who had served in the trenches and believed that this could be avoided by planning for a more mobile war. He believed for instance that the motor-lorry would be the key to military success by maintaining logistical supplies to fast-moving columns of tanks and armoured vehicles, Largely ignored in the UK and France, the tactics he proposed were to prove decisive in the Battle of France. Where the French had built huge, shell-proof redoubts, the German Blitzkrieg forces merely went round them and even outran their support vehicles despite all the planning. The were forced to obtain fuel from ordinary civilian filling-stations and came near grinding to a halt on one or two occasions. It should also be remembered that the Nazis had disseminated massive misinformation through efficient propaganda and were believed to be much stronger than they actually were in military terms and to be a by-word for efficiency, which they certainly were not. The German national and military organisation was incredibly inefficient, but the myth remains to this day.

France spent very little money to build up a modern army. Further, its main tactics were well out of date.

Neither the politics nor the army wanted a conflict. Taking freedom for granted is ludicrous, dangerous even suicidal.

Si vis pacem, para bellum.

Let us not repeat history.

its failure hitler took out all aa weapons and airstrips with bombardments hitler went around the french defenses and hitler got greedy with russia opening up 2 fronts so his forces were split he also wasnt prepared for russian winters

You need to read a book on the history of the beginnings of WWII.