Chapter 23, consisting of seven essays, addressed itself to the question of how best to defend the American people against foreign aggression.
Essential to common defense was the authority to raise armies, build and equip a navy, direct their operations, and provide for their support. The Confederation recognized this but lacked the requisite means to carry it out. To raise men and money, it had to rely on a "fallacious scheme of quotas and requisitions" from the individual states.
There should be a single national government with authority to act without limitation" because of the impossibility of foreseeing the nature and extent of national emergencies, or what means might be required to meet them. If the proposed constitution were adopted, there was no reason to fear that the central government would abuse such unlimited authority.
In Chapter 24, reverting in a rather long essay to the subject of standing armies in times of peace, Hamilton noted that the constitutions of Pennsylvania and North Carolina contained this provision: "as standing armies in time of peace are dangerous to liberty, they ought not to be kept up." The constitutions of Massachusetts, New Hampshire, Maryland, and Delaware contained similar provisions. That was beside the point, argued Hamilton.
Under the proposed constitution, the power of raising military forces would be "lodged in the legislature, not in the executive," and that legislature would consist of representatives periodically elected by the people themselves. That should provide adequate control.
"If we mean to be a commercial people or even to be secure on our Atlantic side, we must endeavour as soon as possible to have a navy." A navy would need dockyards and arsenals, and "moderate garrisons" of a standing military force would be necessary to guard these.
In Chapter 25, a great danger to the country came from the fact that territories of Britain, Spain, and various Indian nations encircled the Union. Some states were more exposed than others. Should such states bear all the weight of measures taken to secure their safety? Or should all states join in defending national security by means "of common councils and of a common treasury"? A standing military force would also be useful in quelling domestic insurrections, such as Massachusetts had recently experienced by Shay's Rebellion.
In Chapter 26, the idea of limiting legislative authority for providing national defense was, in Hamilton's words, "one of those refinements, which owe their origin to a zeal for liberty more ardent than enlightened."
Taking Britain as an example, Hamilton briefly cited what had happened there before, during, and after the Glorious Revolution of 1688, which dethroned James II for tyranny and abuse of authority. For one thing, the king had in time of peace increased the standing army in the kingdom from 5,000 to 30,000 men. After the revolution, the British Parliament framed a Bill of Rights that contained this article: "That the raising or keeping a standing army within the kingdom in time of peace unless with the consent of parliament is against law."
In Chapter 27, a national government along the lines proposed would have less occasion to use force in obtaining compliance with its laws than in a loose confederation with no strong central power.
In Chapter 28, seditious and insurrections now and again occur in all societies and are to the body politic what "tumors and eruptions" are to the human body. If such emergencies arose under the national government, there could be "no remedy but force," with means proportioned to the extent of the "mischief." Individual states through their own militias could themselves handle minor commotions.
In Chapter 29, national security demanded that the central government have the power to regulate the state militias and command their services in times of invasion or insurrection. Uniformity in the organization and discipline of the militias would greatly increase their proficiency on the field of battle. The states would appoint the officers of their militias and have the authority of training such forces "according to the discipline prescribed by Congress." There was no danger to be apprehended to the political rights and civil liberties of the American people by such federal "general superintendence" of the militias.
In these essays, Hamilton wished to substantiate his main lines of argument, which were two: first, that American security depended on a national system of defense under the direction and control of a strong central government; and second, that a well-organized military force would not be a threat to the political liberties and civil rights of the people if, as proposed, all armed forces were placed under the control of the legislature, the Congress, consisting of popularly elected representatives of the people. If such representatives betrayed the people, then the latter would have the right to rise up as they had in their revolution against British rule.