powers denied to the states

-The states are not sovereign governments and so cannot make agreements or otherwise negotiate with forge in states

-This provision relates to foreign, not interstate, commerce. Only congress, not the states, can tax imports; and the states are, like congress, forbidden to tax exports.

-A duty of tonnage is tax laid on ships according to their cargo capacity. Each state has a constitutional right to provide for and maintain a militia; but no state may keep a standing army or navy.