Question

why was the pullman strike effective in the beginning?
the attorney general ordered troops to be sent to protect pullman cars.
the government sided with the striking workers and forced pullman to negotiate.
the union supported the striking workers by boycotting pullman cars nationwide.

Explanation:

The Pullman Strike was effective initially as the union's nationwide boycott of Pullman cars disrupted business operations, putting pressure on the Pullman company. The government did not side with the strikers and the sending of troops was a later - negative development for the strikers.

Answer:

The union supported the striking workers by boycotting Pullman cars nationwide.