Possible Clues:

• They advise you against swapping iodine for nitrogen in explosion
• The trouble-shooting columnists getting grief from State workers
• Columnists getting grief from relatives
• Suffering with relatives? Write to these for advice
• They'd personally advise you to unsay 'Nag' outburst
• Columnists advising previously on state of US relations
• Suffering relatives who try to solve others' problems
• Advice columnists