ARTICLE 1, SECTION 8 - THE CONGRESS SHALL HAVE POWER TO LAY AND COLLECT TAXES, DUTIES, IMPOSTS AND EXCISES...

Short Version -- This is a summary of the important issues covered in this section of the U.S. Constitution.

Congress can lay and collect taxes
Congress can borrow money
Congress can regulate national and international trade
Congress can establish rules for naturalization and bankruptcy laws
Congress can coin money
Congress can set the standard for weights and measures
Congress can punish counterfeiters
Congress can establish post offices and post roads
Congress can grant patents to inventors and copyrights to authors
Congress can set up federal courts
Congress can punish piracy and crimes committed at sea
Congress can declare war
Congress can raise and upport armies
Congress can provide and maintain a navy
Congress can make rules for the government of land and sea forces
Congress can call on the militia (National Guard) to put down rebellion and invasion and to enforce the laws
Congress can help organize, arm, and discipline the militia
Congress can exercise control over the District of Columbia and over other federal property
Congress can make all laws necessary for carrying out its Constitutional powers

Long Version -- This is the text of the Actual U.S. Constitution.

The Congress shall have power to lay and collect taxes, duties, imposts and excises, to pay the debts and provide for the common defense and general welfare of the United States; but all duties, imposts and excises shall be uniform throughout the United States;

To borrow money on the credit of the United States;
To regulate commerce with foreign nations, and among the several states, and with the Indian tribes;
To establish a uniform rule of naturalization, and uniform laws on the subject of bankruptcies throughout the United States;
To coin money, regulate the value thereof, and of foreign coin, and fix the standard of weights and measures;
To provide for the punishment of counterfeiting the securities and current coin of the United States;
To establish post offices and post roads;
To promote the progress of science and useful arts, by securing for limited times to authors and inventors the exclusive right to their respective writings and discoveries;
To constitute tribunals inferior to the Supreme Court;
To define and punish piracies and felonies committed on the high seas, and offenses against the law of nations;
To declare war, grant letters of marque and reprisal, and make rules concerning captures on land and water;
To raise and support armies, but no appropriation of money to that use shall be for a longer term than two years;
To provide and maintain a navy;
To make rules for the government and regulation of the land and naval forces;
To provide for calling forth the militia to execute the laws of the union, suppress insurrections and repel invasions;
To provide for organizing, arming, and disciplining, the militia, and for governing such part of them as may be employed in the service of the United States, reserving to the states respectively, the appointment of the officers, and the authority of training the militia according to the discipline prescribed by Congress;
To exercise exclusive legislation in all cases whatsoever, over such District (not exceeding ten miles square) as may, by cession of particular states, and the acceptance of Congress, become the seat of the government of the United States, and to exercise like authority over all places purchased by the consent of the legislature of the state in which the same shall be, for the erection of forts, magazines, arsenals, dockyards, and other needful buildings;

And To make all laws which shall be necessary and proper for carrying into execution the foregoing powers, and all other powers vested by this Constitution in the government of the United States, or in any department or officer thereof.