A heated exchange between Tucker Carlson and Mark Cuban over immigration turns into a fight about whether the West has changed too fast — a flashpoint that keeps splitting American politics.

• Carlson argues people need stability to marry, have kids, and plan for the future, and that constant upheaval breaks that.
• He points to Los Angeles, saying the city he grew up in is unrecognizable within his own lifetime.
• Cuban pushes back that every generation feels this way, calling it normal rather than radical change.
• Carlson challenges him to name any historical parallel for the scale of population change in the West over the past 50 years.

Outlook: Immigration and demographic change stay at the center of US political argument heading into the next election cycle, with both sides hardening rather than converging.