Tag details: civil defense - history
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LibraryThing tags are composed of aliases, with one alias chosen as the representative or "main" alias. By default, the main alias is the most common English form, calculated from both the number of users and uses. The "Canonical form" allows members to override the most common form, when the most common form is manifestly incorrect or not in English. Members have written comprehensive guidelines for the use of the "Canonical form" field, as well as tag combination.
Because tag combination prompts system-level changes, decisions are now made by votes. See the guidelines for how and when votes are closed and combination effected.
Warnings and disambiguations
Use this field to help other helpers. Read it before doing anything.