Because that's how the founding fathers planned it to be. Nobody has tried to change it so it stays as how it was before
Bangladesh doesn't have any democratic or republican government like US does.
A version of the republican government can be found in the Roman Empire.
the roman republic
It was the only party
Rome
Rome
Because it had a republican form of government prior to the civil war. The fundamental form of the US government has not changed since its formation 234 years ago.
a republican form of government.
All states in the US have a republican government system.
pure democracy
Article IV, Section 4 of the US Constitution states:"The United States shall guarantee to every State in this Union a Republican Form of Government, . . . "Note that the words "Republican Form of Government" were capitalized in the US Constitution itself, making it crystal clear that a particular form of government is both mentioned in and guaranteed by the Constitution.
A constitutional republic. Republican