We need an America with the wisdom of experience. But we must not let America grow old in spirit.

Humphrey contrasts two kinds of “age” in a nation: the valuable maturity that comes from lived experience, and the dangerous stagnation that comes from cynicism, fear, or resistance to change. The first—“wisdom of experience”—suggests learning from past mistakes and building institutions that reflect hard-won knowledge. The second—“grow old in spirit”—warns against losing moral energy, imagination, and commitment to reform. In Humphrey’s political idiom, the line reads as a call for pragmatic progressivism: honor tradition and lessons of history, but keep the country’s civic ideals youthful—open, hopeful, and willing to extend rights and opportunity.