Is federalism necessary? (do not use google since the last person did and I don't understand that response)

Federalism is very necessary in maintaining one system that allows for citizens to participate in his or her's government.  This creates more power in the citizens' hands to influence policies that they can agree on so that power is shared.

Explanation:

according to this text from the preamble to the declaration, who gives men their unalienable rights?

there are hundreds of postives ways to unite a country with another country here are a   few

1 peace treaty's peace treatys

are basically a document signing a allliance with one country and another.

2 gift

what i mean by this is for example how the french gave the americans the statue of libery a gift of peace.