Shipyard workers requested for pay increase due to escalated inflation. the employers did not heed the requests by the workers and therefore a strike ensued, with over 600k workers taking part, paralysing the city.
The Seattle General Strike happened in 1919 and lasted 5 days. It was a general work stoppage that involved 65 thousand workers of many types of work. The Strike started when several unions came together to ask for higher wages since the WWI imposed wages controls, but the cost of living went up since WWI brought major changes to Seattle, making it develop quickly.
Its a significant American event because of the rarity of a president being impeached. There have only been 2 impeached in History(3 if you count Richard Nixon but he resigned during Impeachment Trials)
As for Britain's response, it was initially no more than the dropping of anti-Nazi propaganda. leaflets-13 tons of them- over Germany. They would begin. bombing German ships on September 4, suffering significant losses.