Why was the necessary and proper clause included in the constitution

It gave Congress the flexibility to make laws as time progressed and unforeseen issues came up in the development of the US.

The "necessary and proper" clause is included in the Constitution under the legislative powers. It allows Congress to create laws both reflecting explicit powers and implied powers of the Constitution. This clause has allowed Congress to create laws needed as the US expanded, technology changed, and the US was presented with crisis situations such as the Civil War.

The "necessary and proper" clause is also referred to as the Elastic Clause. It has been used to create a National Bank, create federal offices and positions, and even been used to execute laws against piracy. This clause has allowed the use Constitution to grow and change in its scope without actually changing the document.