Answer:
The persuasive technique that is used in the passage from "The Crisis", by Thomas Paine, is the following one:
Appeal to emotion.
Explanation:
One can tell there is appeal to emotion both by the word choice (intense and full of effect: blood, curse, cowardice) and the meaning as a whole ("the blood of his children", which sounds intense and strong). The sentence causes the reader to have an awkward feeling, a mixture of anger and sorrow, and those are certainly emotions.
