What does a federal system do that a state system can not?

Answer 1

You might find this useful:

http://bensguide.gpo.gov/9-12/government/federalism.html


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National Government

* Print money
* Regulate interstate (between states) and international trade
* Make treaties and conduct foreign policy
* Declare war
* Provide an army and navy
* Establish post offices
* Make laws necessary and proper to carry out the these powers


State Governments

* Issue licenses
* Regulate intrastate (within the state) businesses
* Conduct elections
* Establish local governments
* Ratify amendments to the Constitution
* Take measures for public health and safety
* May exert powers the Constitution does not delegate to the national government or prohibit the states from using

In addition to their exclusive powers, both the national government and state governments share powers. Shared powers between the national government and state governments are called concurrent powers. Current powers of the national government and state governments include the ability to:

* Collect taxes
* Build roads
* Borrow money
* Establish courts
* Make and enforce laws
* Charter banks and corporations
* Spend money for the general welfare
* Take private property for public purposes, with just compensation

Answer 2

There is a thing call jurisdiction where federal law enforcement agencies investigate and handle federal crimes, and the state handles state crimes

Answer 3

Lets see declare war on another country, take income tax, try you for treason, make lwas that effect the whole country, control interstate trade and a whole alot more i don't feel like listing.

Answer 4

Issue currency, make treaties and then some.