What did it take so long for us troops to entercombat

Reason as it took so long for US troops to enter-combat:

General Pershing sent the soldiers to the east of France for further training.  This took so much time for American troops to fight as General Pershing sent soldiers for training in eastern France for further preparation to be able to combine with British and French soldiers with a very large German army of 260 divisions.

In compliance with the petition of the UK and France, as a result of a powerful German offensive, the President decides that, should the need arise; the American forces should combine with the French and British armies, as little as the companies around the world. The solution comes in the form of an agreement signed in Dec, 1917.

look ongoog you might find it

depends on the age of the teen, many believe by the age of 16 a person should know the strong difference between right and wrong along with the difference between risky and immediate death. swimming with sharks might be dangerous but swimming with sharks while bloody meat is attached to you is just insane. even more if you have no idea what you're doing. however, no matter the age, as long as the person is skilled enough and has the mental and physical capacity to control their actions doing whatever sport they put their mind to is all that matters.