Antifederalist Papers http://teachingamericanhistory.org/library/index.asp?subcategory=73 John DeWitt IV http://teachingamericanhistory.org/library/index.asp?document=1649 (1787)
Attributed
Context: It is asserted by the most respectable writers upon Government, that a well regulated militia, composed of the yeomanry of the country have ever been considered as the bulwark of a free people; and, says the celebrated Mr. Hume, "without it, it is folly to think any free government will have stability or security. When the sword is introduced, as in our constitution (speaking of the British) the person entrusted will always neglect to discipline the militia, in order to have a pretext for keeping up a standing army; and it is evident this is a mortal distemper in the British parliament, of which it must finally inevitably perish."
“No free government under Heaven, with a well disciplined militia was ever yet subdued by mercenary troups.”
Antifederalist Papers http://teachingamericanhistory.org/library/index.asp?subcategory=73 John DeWitt IV http://teachingamericanhistory.org/library/index.asp?document=1649 (1787)
Attributed
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“Under the present government all ranks of people are subject to militia duty.”
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Context: Mr. Chairman — A worthy member has asked, who are the militia, if they be not the people, of this country, and if we are not to be protected from the fate of the Germans, Prussians, &c. by our representation? I ask who are the militia? They consist now of the whole people, except a few public officers. But I cannot say who will be the militia of the future day. If that paper on the table gets no alteration, the militia of the future day may not consist of all classes, high and low, and rich and poor; but may be confined to the lower and middle classes of the people, granting exclusion to the higher classes of the people. If we should ever see that day, the most ignominious punishments and heavy fines may be expected. Under the present government all ranks of people are subject to militia duty.

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Context: A well-disciplined militia is a safe, an honorable guard to a community like this, whose inhabitants are by nature brave, and are laudably tenacious of that freedom in which they were born. From a well-regulated militia we have nothing to fear; their interest is the same with that of the State. When a country is invaded, the militia are ready to appear in its defense; they march into the field with that fortitude which a consciousness of the justice of their cause inspires; they do not jeopard their lives for a master who considers them only as the instruments of his ambition, and whom they regard only as the daily dispenser of the scanty pittance of bread and water. No; they fight for their houses, their lands, for their wives, their children; for all who claim the tenderest names, and are held dearest in their hearts; they fight pro aris et focis, for their liberty, and for themselves, and for their God.

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Source: The Constitution of the United States of America

House of Representatives, Amendments to the Constitution, 17, 20 Aug. 1789 http://press-pubs.uchicago.edu/founders/documents/amendIIs6.html