Fires built as an obstructionist tactic (10)
I believe the answer is:
filibuster
'an obstructionist tactic' is the definition.
Although both the answer and definition are singular nouns, I don't see how they can define each other.
'fires built' is the wordplay.
'fires built' anagrams to 'FILIBUSTER'.
However, I'm not clear how this is indicated.
'as' is the link.
Can you help me to learn more?
(Other definitions for filibuster that I've seen before include "Speak at length to obstruct parliamentary proceedings" , "Delaying tactic to obstruct legislation" , "delaying tactics" , "delaying manoeuvre" , "Waste time by making long speeches" .)