Look for fuel trucks. A gasoline fire would do to the Golden Gate cables what jet fuel did to the WTC steel girders ... melt them. The bridge would fall.
Answer: stop all trucks.
Delay them for 24 hours. Put our own drivers in for the bridge crossing. Let the original drivers take a bus across.
This requires military thinking. Lawyers need not apply.
The (only) bridge to South Padre Island, TX was taken out by a tug boat pulling (or pushing?) 4 barges. Happened a week or two after 9/11. It'll be out of commission until December.