Article 2, Section 2, Clause 1
Joseph Story, Commentaries on the Constitution 3:§§ 1485--861833
§ 1485. The command and application of the public force, to execute the laws, to maintain peace, and to resist foreign invasion, are powers so obviously of an executive nature, and require the exercise of qualities so peculiarly adapted to this department, that a well-organized government can scarcely exist, when they are taken away from it. Of all the cases and concerns of government, the direction of war most peculiarly demands those qualities, which distinguish the exercise of power by a single hand. Unity of plan, promptitude, activity, and decision, are indispensable to success; and these can scarcely exist, except when a single magistrate is entrusted exclusively with the power. Even the coupling of the authority of an executive council with him, in the exercise of such powers enfeebles the system, divides the responsibility, and not unfrequently defeats every energetic measure. Timidity, indecision, obstinacy, and pride of opinion, must mingle in all such councils, and infuse a torpor and sluggishness, destructive of all military operations. Indeed, there would seem to be little reason to enforce the propriety of giving this power to the executive department, (whatever may be its actual organization,) since it is in exact coincidence with the provisions of our state constitutions; and therefore seems to be universally deemed safe, if not vital to the system.
§ 1486. Yet the clause did not wholly escape animadversion in the state conventions. The propriety of admitting the president to be commander-in-chief, so far as to give orders, and have a general superintendency, was admitted. But it was urged, that it would be dangerous to let him command in person without any restraint, as he might make a bad use of it. The consent of both houses of congress ought, therefore, to be required, before he should take the actual command. The answer then given was, that though the president might, there was no necessity, that he should, take the command in person; and there was no probability, that he would do so, except in extraordinary emergencies, and when he was possessed of superior military talents. But if his assuming the actual command depended upon the assent of congress what was to be done, when an invasion, or insurrection took place during the recess of congress? Besides, the very power of restraint might be so employed as to cripple the executive department, when filled by a man of extraordinary military genius. The power of the president, too, might well be deemed safe; since he could not, of himself, declare war, raise armies, or call forth the militia, or appropriate money for the purpose; for these powers all belonged to congress. In Great Britain, the king is not only commander-in-chief of the army, and navy, and militia, but he can declare war; and, in time of war, can raise armies and navies, and call forth the militia of his own mere will. So, that (to use the words of Mr. Justice Blackstone) the sole supreme government and command of the militia within all his majesty's realms and dominions, and of all forces by sea and land, and of all forts and places of strength, ever was and is the undoubted right of his majesty; and both houses or either house of parliament cannot, nor ought to pretend to the same. The only power of check by parliament is, the refusal of supplies; and this is found to be abundantly sufficient to protect the nation against any war against the sense of the nation, or any serious abuse of the power in modern times.[Volume 4, Page 12]
OPINIONS IN WRITING
The Founders' Constitution
Volume 4, Article 2, Section 2, Clause 1, Document 12
The University of Chicago Press
Story, Joseph. Commentaries on the Constitution of the United States. 3 vols. Boston, 1833.