the obstacle the kept the 21st division the allies on D-day was a river called the Orne river
Getting off the well defended beaches seems to have been the greatest obstacle. Once that happened advance was inexorable.
The 21st Panzer Division was hindered by the difficult terrain of the Norman countryside, particularly the dense hedgerows and the steep, uneven landscape. This made rapid movement and coordination challenging for armored units. Additionally, the division faced delays due to a lack of clear orders and the disruption caused by the Allied airborne landings, which further impeded their ability to respond effectively on D-Day.
In the D-Day invasion the Allied armies, US, Britain, Canada and smaller numbers of many Allies were attacking German Armies holding Europe.
Russia helped the war effort on the western front in the world war 1 because in the ww1 Russia wanted to save it's allies and austria-hungary were attacking their ally that's why they entered to help their allies in the war. They attacked Germany on their front which is called the eastern front, the Russians were failing because Germans were attacking them but the Russians had many soldiers and weapon to defend their country on their front.
the obstacle the kept the 21st division the allies on D-day was a river called the Orne river
Getting off the well defended beaches seems to have been the greatest obstacle. Once that happened advance was inexorable.
German fortifications..................
It was slightly above a large Axis territory where the Allies had a good attacking point.
The largest and most formidable obstacle was the Atlantic Wall, a "wall" of defenses stretching the entire coast of the Atlantic.
The Allies were the enemies of Germany; attacking them was a prudent act of war.
The Allies gained air superiority by attacking German supply depots and airfields. By D-Day there was virtually no Luftwaffe in the air.
so they could get the Germans out of North Africa.
N. Vietnam was ATTACKING S. Vietnam. South Vietnam was defending itself with the help of the US/Allies.
Japan sought a true surprise attack and did not share this information for fear of it being compromised .
England had joined the Great War when they Declared on Germany for attacking both Belgium and France who were Britains allies
The Italians betrayed their German and Austrian allies in the Triple Alliance by attacking Austria in May 1915. Italy thus joined France, Great Britain, and Russia, who had formed the Triple Entente, but now were called the Allied Powers, or Allies.