US politicians in both parties are fumbling basic questions about Taiwan, and that is bad news for anyone counting on clear American deterrence in the Pacific.

• A sitting Republican senator from South Carolina admitted during a primary debate that she doesn't know much about national security when asked about Taiwan.
• Her Republican rival leaned on slogans about peace through strength and chips, blaming Democrats for any Chinese takeover.
• On the Democratic side, AOC gave a vague answer at the Munich Security Conference about whether the US should help defend Taiwan.
• The Wall Street Journal argues what actually deters Beijing is military strength and the willingness to use it, not praise for Trump.
• A Chinese blockade or invasion of Taiwan would hit the US economy far beyond lost chip production.

Outlook: Taiwan is set to become a test question in US Senate and presidential campaigns, and so far most candidates are failing it.