The Constitution fixed the problems of the Articles of Confederation by the following. Article I of the Constitution, Congress can regulate interstate commerce. It is also responsible for coinage and only Congress can regulate tariffs; in the early days of the national government, it was largely funded through land sales, excise taxes, and tariffs. Article II gave the national government a chief executive whose job it was to execute the laws. He had veto power over Congress, but Congress could override his veto or even vote to impeach him in extreme cases.