Article 1, Section 10, Clause 3

Document 1

Articles of Confederation, arts. 6, 9

Article VI. No vessels of war shall be kept up in time of peace by any state, except such number only, as shall be deemed necessary by the united states in congress assembled, for the defence of such state, or its trade; nor shall any body of forces be kept up by any state, in time of peace, except such number only, as in the judgment of the united states, in congress assembled, shall be deemed requisite to garrison the forts necessary for the defence of such state; but every state shall always keep up a well regulated and disciplined militia, sufficiently armed and accoutred, and shall provide and constantly have ready for use, in public stores, a due number of field pieces and tents, and a proper quantity of arms, ammunition and camp equipage.

No state shall engage in any war without the consent of the united states in congress assembled, unless such state be actually invaded by enemies, or shall have received certain advice of a resolution being formed by some nation of Indians to invade such state, and the danger is so imminent as not to admit of a delay till the united states in congress assembled can be consulted: nor shall any state grant commissions to any ships or vessels of war, nor letters of marque or reprisal, except it be after a declaration of war by the united states in congress assembled, and then only against the kingdom or state and the subjects thereof, against which war has been so declared, and under such regulations as shall be established by the united states in congress assembled, unless such state be infested by pirates, in which case vessels of war may be fitted out for that occasion, and kept so long as the danger shall continue, or until the united states in congress assembled, shall determine otherwise.

. . . . . ???tinue, or until the united states in congress assembled, shall determine otherwise.

Article IX. The united states in congress assembled, shall have the sole and exclusive right and power of determining on peace and war, except in the cases mentioned in the sixth article--of sending and receiving ambassadors--entering into treaties and alliances, provided that no treaty of commerce shall be made whereby the legislative power of the respective states shall be restrained from imposing such imposts and duties on foreigners as their own people are subjected to, or from prohibiting the exportation or importation of any species of goods or commodities whatsoever--of establishing rules for deciding in all cases, what captures on land or water shall be legal, and in what manner prizes taken by land or naval forces in the service of the united states shall be divided or appropriated--of granting letters of marque and reprisal in times of peace--appointing courts for the trial of piracies and felonies committed on the high seas and establishing courts for receiving and determining finally appeals in all cases of captures, provided that no member of congress shall be appointed a judge of any of the said courts.

The Founders' Constitution
Volume 3, Article 1, Section 10, Clause 3, Document 1
http://press-pubs.uchicago.edu/founders/documents/a1_10_3s1.html
The University of Chicago Press