Woo Hoo! We Didn't Violate Any Treaties!

That's right: our use of white phosphorous--an agent which many would call a chemical weapon, given its painful internal suffocation of victims--was OK because we never signed the international treaty regulating its use.

Here are two (out of order) bits from the BBC's Q&A on the material:

Some have claimed the use of white phosphorus contravenes the 1993 Chemical Weapons Convention. This bans the use of any "toxic chemical" weapons which causes "death, harm or temporary incapacitation to humans or animals through their chemical action on life processes".

Professor Paul Rogers, of the University of Bradford's department of peace studies, told the BBC that white phosphorus could probably be considered a chemical weapon if deliberately aimed at civilians.

And:

Washington is not a signatory to any treaty restricting the use of white phosphorus against civilians.

White phosphorus is covered by Protocol III of the 1980 Convention on Conventional Weapons, which prohibits its use as an incendiary weapon against civilian populations or in air attacks against enemy forces in civilian areas.

The US - unlike 80 other countries including the UK - is not a signatory to Protocol III.