f I were a federalist I would be all in for the constitution. Federalists favour states unity under one central government, in this case our federal government. There's more order that way. The states can have their own laws while still abiding by the central government laws, and it keeps everything organized. Federalists would argue in support of the US constitution since it would unify all states under one government, making it easier to regulate trade between states, and keep order within the whole country, opposed to having several states that do their own thing. In order to build a strong country, everyone needs to be on the same page, therefore the US constitution must be drafted and that states must be unified.