Preparing for war takes place over a matter of months, if not years. This is true physically, logistically, and psychologically. Basically, the Germans were ready for war in September 1939, the Allies were not.

One advantage enjoyed by the German army was the "practice" it had obtained in the occupation of both Austria and the modern Czech Republic (Slovakia became a satellite state). There was no resistance, but an occupation is an occupation, and the German army worked out a number of logistical bugs. The Allied armies had no similar experience.

Then there was Poland, a flat land made for German tanks in ideal (non hot, non rainy) early fall weather. Imagine a Germany army on the Polish border at the race track, supplies and ammunition in place, ready to charge across the starting line at top speed as soon as the starting gun goes off, crushing everything standing its way. With some help from the Soviet Union (totally unexpected by the Allies), the Germans are across Poland in about 30 days.

On the other side, you do have Allied armies with about a 5 to 1 numerical advantage against German defenders of the Siegfried line. A fifth of those troops are in Britain, across the English Channel, and will require time to deploy. Their symbolic importance is greater than their numerical importance, because the French won't move without them.

And the Allies weren't "at the race track," but at home, "heading down to the track." They could, and did cross the German border, but the experience of World War I had taught them that even with a 5-to-1 advantage, defeating a fortified enemy would take some time, certainly more than a month. And suppose they began to get the better of the defenders of the Siegfried line...

Buoyed by their recent victory, the invaders of Poland would have hurried back across Germany and smashed the Allied attack in late fall, possibly causing as much or more damage as they did in the invasion of France. On the other hand, the French experience (pre tank) was that they could hold on for a long time in a defensive war, which is the war they adopted.

Preparing for war takes place over a matter of months, if not years. This is true physically, logistically, and psychologically. Basically, the Germans were ready for war in September 1939, the Allies were not.

One advantage enjoyed by the German army was the "practice" it had obtained in the occupation of both Austria and the modern Czech Republic (Slovakia became a satellite state). There was no resistance, but an occupation is an occupation, and the German army worked out a number of logistical bugs. What's more, they got the benefit of Austrian and Czech weapons-producing capability. The Allied armies had no similar experience.

Then there was Poland, a flat land made for German tanks in ideal (non hot, non rainy) early fall weather. Imagine a Germany army on the Polish border at the race track, supplies and ammunition in place, ready to charge across the starting line at top speed as soon as the starting gun goes off, crushing everything standing its way. With some help from the Soviet Union (totally unexpected by the Allies), the Germans are across Poland in about 30 days.

On the other side, you do have Allied armies with about a 5 to 1 numerical advantage against German defenders of the Siegfried line. A fifth of those troops are in Britain, across the English Channel, and will require time to deploy. Their symbolic importance is greater than their numerical importance, because the French won't move without them.

And the Allies weren't "at the race track," but at home, "heading down to the track." They could, and did cross the German border, but the experience of World War I had taught them that even with a 5-to-1 advantage, defeating a fortified enemy would take some time, certainly more than a month. And suppose they began to get the better of the defenders of the Siegfried line...

Buoyed by their recent victory, the invaders of Poland would have hurried back across Germany and smashed the Allied attack in late fall, possibly causing as much or more damage as they did in the invasion of France. On the other hand, the French experience (pre tank) was that they could hold on for a long time in a defensive war, which is the war they adopted.