Some relevant quotes:

 

The US is one of
    the countries to have filed the legal instruments of the
    Biological Weapons Convention signed in 1972 - the first
    international treaty banning weapons of this kind. It has
    no system of verification, but five-yearly revision
    conferences have brought progress in that direction. At
    the 1991 meeting in Geneva, for example, groups of
    experts were set up to propose improvements; this was an
    initiative by France and a number of other western
    countries

    Their 10 years of work came to nothing when, on 25 July
    2000, the US Assistant Secretary of State for
    proliferation rejected all the new proposals on the
    grounds that they were contrary to US commercial and
    security interests (he meant the US programme for defence
    against biological weapons) and said they did not
    guarantee any slowing in the proliferation of such
    weapons.

 

At least the Chemical Weapons Convention (CWC), signed in
    1993, does have a system of verification. But the US did
    not ratify it until April 1997. And Congress introduced
    new provisions watering down what US negotiators had
    themselves insisted on (3).

 

Although in May 2000 the US deposited the declaration all
    signatory countries were required to make, the first
    inspections in the US went badly. The OPCW inspectors saw
    many of their requests frustrated by red tape (4). The
    US, which had demanded transparency from proliferators
    acted like any suspect administration. So it is hardly
    surprising that Iraq, South Korea, Russia and Iran
    adopted, almost verbatim, US reservations about the CWC.

                     The Conference on the Illicit Trade in Small Arms and
    Light Weapons (5) has still not produced any results, It
    took place in New York in July last year under pressure
    from non-governmental organisations (NGOs) to stop the
    "slaughter of the poor". It is up against powerful US gun
    lobbies; they invoke constitutional guarantees (fourth
    amendment on the right of US citizens to be secure in
    their persons). The US continues to reject any binding
    legal rule and any ban on transfers to non-state players
    so it can continue supporting pro-American guerrillas

    .

    Little by little, the international edifice built in an
    age of two superpowers, balanced forces and mutually
    assured destruction is crumbling

 

This dismantling did not begin with the present
    Republican administration. The difference between Bush
    and his predecessor lies more in the way he treats his
    main allies.