In USA Why can’t we set a maximum sentence 2 weeks in jail no matter what crime committed ?

'Cause we don't want serial killers walking around our streets. 

Mostly because of the Constitution, and also because that idea is stupid.  That would actually encourage crime.  Murder someone, do two weeks, move on.  Sounds....not smart.

There is nothing preventing the law makers of doing so, but in their wisdom they realize that lowering punishments and the ease of paying bail would end civilized society.

What do you think would happen when someone commits a murder knowing the punishment is only "two weeks in jail?"

oh, good -- so then I could murder the rapist and only serve 14 days -- that'll work real well -- after that, the proverbial Hatfields and McCoys feud will look like it was child's play

Is there, at any point in this 2-week maximum sentence, an execution involved?  

You didn't say.  

That is is too excessive according to some Democrats.

They want no bail and no jail 

Cons say if a black man passes a counterfeit bill he needs to be publicly choked dead.