The US is preparing to use the toxic riot-control agents CS gas and pepper spray in Iraq in contravention of the Chemical Weapons Convention, provoking the first split in the Anglo-US alliance. "Calmative" gases, similar to the one that killed 120 hostages in the Moscow theatre siege last year, could also be employed.
The convention bans the use of these toxic agents in battle, not least because they risk causing an escalation to full chemical warfare. This applies even though they can be used in civil disturbances at home: both CS gas and pepper spray are available for use by UK police forces. The US Marine Corps confirmed last week that both had already been shipped to the Gulf.
It is British policy not to allow troops to take part in operations where riot control agents are employed. But the US Defence Secretary, Donald Rumsfeld, has asked President Bush to authorise their use. Mr Bush, who has often spoken of "smoking out" the enemy, is understood to have agreed.
Internal Pentagon documents also show that the US is developing a range of calmative gases, also banned for battlefield use. Senior US defence sources predict these could be used in Iraq by elite special forces units to take out command and control bunkers deep underground.
Rear Admiral Stephen Baker, a Navy commander in the last Gulf War who is now senior adviser to the Centre for Defence Information in Washington, told The Independent on Sunday that US special forces had knock-out gases that can "neutralise" people. He added: "I would think that if they get a chance to use them, they will."
The Pentagon said last week that the decision to use riot control agents "is made by the commander in the field".
Mr Rumsfeld became the first senior figure on either side of the impending conflict to announce his wish to use chemical agents in a little-noticed comment to the House of Representatives Armed Services Committee on 5 February - the same day as Colin Powell's presentation of intelligence about Iraq's weapons of mass destruction to the UN.
The Defence Secretary attacked the "straitjacket" imposed by bans in international treaties on using the weapons in warfare. He specified that they could be used "where there are enemy troops in a cave [and] you know there are women and children in there with them". General Richard Myers, chairman of the US Joint Chiefs of Staff, spoke of using them against human shields.
The revelations leave the Bush administration open to charges of double standards at a time when it is making Iraq's suspected arsenal of chemical and biological weapons the casus belli. Charles Kennedy, leader of the Liberal Democrats, said last night: "This all adds to the confusion over how the war will be conducted. If the argument with Saddam Hussein is over disarming him of weapons of mass destruction, it is perverse of the US to push the boundaries of international chemical warfare conventions in order to subdue him."
Leading experts and Whitehall officials fear that using even pepper spray and CS gas would destroy the credibility of the Chemical Weapons Convention, provoke Iraqi chemical retaliation and set a disastrous legal precedent. Professor Julian Perry Robinson, one of the world's foremost authorities on the convention, said: "Legally speaking, Iraq would be totally justified in releasing chemical weapons over the UK if the alliance uses them in Baghdad.
"When the war is over and these things have been used they will have been legitimised as a tool of war, and the principle of toxic weapons being banned will have gone. The difference between these weapons and nerve gas is simply one of structural chemistry."
The Ministry of Defence has warned the US that it will not allow British troops to be involved in operations where riot control agents are used, or to transport them to the battlefield, but Britain is even more concerned about the calmatives. This is shown by documents obtained by the Texas-based Sunshine Project under the US Freedom of Information Act. These reveal that the US is developing calmatives - including sedatives such as the benzodiazapines, diazepam, dexmeditomide and new drugs that affect the nervous system - even though it accepts that "the convention would prohibit the development of any chemically based agent that would even temporarily incapacitate a human being".
A special working group of the Federation of American Scientists concluded last month that using even the mildest of these weapons to incapacitate people would kill 9 per cent of them. It added: "Chemical incapacitating weapons are as likely as bullets to cause death."
The use of chemical weapons by US forces was explicitly banned by President Gerald Ford in 1975 after CS gas had been repeatedly used in Vietnam to smoke out enemy soldiers and then kill them as they ran away. Britain would be in a particularly sensitive position if the US used the weapons as it drafted the convention and is still seen internationally as its most important guardian.
The Foreign Office said: "All states parties to the Chemical Weapons Convention have undertaken not to use any toxic chemical or its precursor, including riot-control agents. This applies in any armed conflict."
2 March 2003 00:03