US watching Pak nukes

It is also looking at ways to prevent the Al Qaeda or extremists within the Pakistani military or intelligence services from gaining access to the country’s weapons and fissile material. ‘‘It’s what we don’t know that worries us,’’ said a senior US official, ‘‘including the critical question of how much fissile material Pakistan now holds — and where.’’ Three years ago, US officials estimated Pakistan had enough highly enriched uranium to manufacture 40 nuclear weapons. It is assumed that the figure has grown. ‘‘It’s one of the things that we’re concerned about — nuclear materials or related information falling into the hands of terrorists or states who harbour them,’’ a State Department official said.

Under US President George W. Bush and his predecessor, Bill Clinton, the Pentagon has analysed whether US forces could seize or secure Pakistan’s nuclear arsenal if it appeared likely to fall into the hands of terrorists or their sympathisers. But a number of administration officials said they had concluded it was impossible to be certain where all of Pakistan’s nuclear materials and weapons components were stored. One Pentagon official said any raid to secure Pakistan’s nuclear arsenal during a period of chaos would be ‘‘a highly risky venture’’.

The degree of the US’ possible involvement in that process is a secret, in part because the Bush administration does not want to exacerbate anti-US sentiment in Pakistan.

But there are other reasons, administration and Pentagon officials say. Pakistan has not signed the Nuclear Non-proliferation Treaty, and so the US is prohibited from sharing certain technology. In addition, the US’ computerised, encoded nuclear safeguards are among the nation’s most prized secrets. Pakistan, too, might reject an offer of the safeguard technology, because it would have to share its own nuclear design secrets with the US.