An Arms-Build up would lead to peace due quite frankly, to fear. It would lead to peace, just like for example, North Korea. No one is allowed to have weaponry, meaning fear. No one attempts to revolt, due to fear. Having a militia, would enforce fear, causing no revolts, or riots, or anything of the sort.
Based on the sentence of the excerpt,
The main purpose of the final sentence from Thomas Paine's common sense would be :
To indicate that the American colonies can establish a better government thana monarchy
Hope this helps
The vice president becomes president
<u><em>Oneness, Purity, Parenting, and Love.</em></u>
<em />
