Newly-appointed US Defence Secretary, Donald Rumsfeld, is a veteran Republican official whose government service dates back to the Nixon administration.

In fact, he has already served as defence secretary once before, under President Gerald Ford.

In some ways he was an unexpected choice for defence.

Former Senator Dan Coats had been widely tipped for the job.

But one of the reasons he was chosen was to deal with the complex personal chemistry of the Bush administration's foreign policy team.

Youngest and oldest ever

When Mr Rumsfeld first became defence secretary in 1975, he was the youngest person ever to hold that post.

Today at 68 years of age, he is probably one of, if not, the oldest ever.

During the intervening time, the world has changed out of all recognition, but Mr Rumsfeld has maintained a continuing interest in security issues.

Some two years ago, he headed a commission that reported on the growing missile threat to the United States and he is likely to be a strong supporter of Mr Bush's missile defence plans.

Strong on defence

More recently he criticised the Clinton administration for its failure to block Russian arms sales to Iran.

But quite apart from his policy position, it is his seniority and experience that have made him Mr Bush's choice to head the Pentagon.