Implied powers are authoritative actions that aren't specifically granted to Congress in the Constitution but are considered necessary to fulfill governmental duties. For example, the Constitution allows Congress to raise an army, which is known as an "expressed power." Using a mandatory draft to recruit soldiers is an implied power.
The implied powers allow Congress to draft new laws at will, especially if the legislation protects the general populace or is considered crucial for upholding laws defined by the expressed powers. The founding fathers who were in favor of this policy wanted to ensure that the federal government could adapt its powers to changing needs and take action to address unforeseen problems. However, the vague definition of the implied powers has created controversy when new laws threaten to impose upon civil rights.