Possible Clues:

• Dispel differences
• Defuse a tense situation
• Attempt to erase discord produced by awful cheater and liar
• Remove uncertainty
• Hear article rewritten to defuse tension
• Reduce hostilities ... or what one must do to each starred clue
• Settle misunderstanding, showing one way to reduce pollution?
• To simplify the condition, get rid of smog
• Harriet and Alec arranged to relieve tension
• Extractor fan could defuse the situation