Freedom of speech is a basic foundation of a free society. Burning books leads to burning people.
It should never be illegal to own a book such as "The Poor Man's James Bond" or "The Anarchist's Cookbook". The idea that one could be jailed for merely owning "material that could be of use to terrorists" is abhorrent in a free society. Should we criminalise maps because terrorists could use them to plan attrocities? Why then should we criminalise these books? Reading them does not make one a terrorist any more than owning a map of London.