The United States gained independence from the British!
I DECLARE INDEPENDENCE!
Unfortunately, the US created a shoddy government.
We need a new government!
The Articles of Confederation stink!
Big changes were in order.
Hmm, we need a new set of laws! We need freedom, the right to bear arms, no quartering of soldiers, no search without warrant, the right to remain silent, right to a quick trial, a trail with a jury, no cruel punishment, more rights than these, AND rights not given to the government be given to the states!
The Declaration of Independence
Said changes were carefully overseen and all that to ensure it wouldn't fall flat again.
We will make sure that no one part of the new government will have more power than the others.
Articles of Confederation/Constitutional Convention
The new government was a success thanks to its divided government.