These martyrs of patriotism gave their lives for an idea.

Colfax’s line frames fallen soldiers (or political victims) as “martyrs,” emphasizing that their deaths were not merely for territory or personal gain but for a governing principle—an “idea” such as union, liberty, or republican self-government. The phrasing elevates patriotism into the realm of moral witness: to die for an idea is to affirm its worth beyond individual life. It also functions rhetorically to bind listeners to that idea, implying an obligation to honor the sacrifice by sustaining the cause. The quote’s power lies in its compression: it turns complex political conflict into a stark ethical contrast between transient lives and enduring principles.