Well dont you mean what they wear well they wear normal clothes like me and you that i know of .
Because the Japanese needed to expand their empir. The French, Dutch, British, Astralians and Americans all occupied the region. The French, Dutch and British were all fighting for their lives in Europe so Japan just walked in and took their colonies. The Astralians were not prepared to fight a war without British help since Astralia was just a colonie with alot of independence. America was the biggest and pretty much the only threat to Japan their was. Japan could not deafet the U.S. because America's industrial cupacity was to strong and the U.S. outnumbered Japan so badly. Japan belived that if the could cripple the U.S. Pacific Fleet then the U.S. couldn't react to Japanese agresson in Pacific.Why did Japan attack at all? Because they thought America would eventauly enter the war against them any how.
France was the major Allied power in WW1. France had the biggest army in the world. (In the Western Front yes, Russia however was also a member of the Triple Entente alliance and commanded an army - 1,400,000 twice the size of France - 739,000 as at mobilisation in 1914) After early defeats, the French, helped by the British, stopped the Germans before they could reach Paris and both sides began to dig trenches. The French and British armies suffered HUGE losses because of the stupidity of their commanders, the French lost 1 500 000 soldiers, and the British 800 000. The French were the victors of the longest battle of WW1, the Battle of Verdun, where 500 000 French soldiers died. To lift some pressure off of the French army at Verdun, British and French troops started the Battle of the Somme, which has been a total slaughter and a failure, but allowed the French to resist the Germans at Verdun. After the Americans arrived, exhausted French and British armies recovered hope, and, under of the command of the Frenchman Ferdinand Foch, supreme commander of the Allied forces, passed through the German lines and defeated definitively Germany, which surrendered the 11th of November. The War lasted 4 years. In WW2, the French, who had been traumatized by WW1, used the same tactic that in WW1, now totally outdated in front of the German unstoppable Blietzkrieg, and were defeated in only 6 weeks. They surrendered to Hitler to prevent the death of millions of civilians if France conitnued the war.