Why did Britain declare war on Germany?

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Tags

1. #declared
2. #threat
3. #serious
4. #through
5. #german
6. #belgium
7. #august
8. #ports
9. #france
10. #british
11. #attacked
12. #hours
13. #ignore
14. #germany
15. #within
16. #events
17. #refused
18. #control
19. #would
20. #britain
21. #close
22. #coast