Controversial Muslim cleric Abu Hamza al-Masri was part of a “global conspiracy to wage Jihad” against the West, US government lawyers claim.
Mr Hamza, 46, is at Belmarsh Magistrates’ Court for a hearing to decide whether he should be extradited to face US terrorism charges.
The London-based preacher has been in custody since May.
His lawyers are likely to argue the hearing should be adjourned to allow more time to prepare his defence.
Nine charges are being considered by a district judge at the high-security court.
One charge relates to organising a kidnapping in Yemen in 1998, which led to the deaths of four hostages.
He was also accused of trying to set up a terrorist camp in the US to train people to fight in Afghanistan.
James Lewis QC, representing the US, told the court: “Abu Hamza is a member of a global conspiracy to wage Jihad against the United States and other countries.
“He has consistently advocated hatred and violence against the United States of America, which he called the United Snakes of America.”
It is the first hearing of a process that could take many months, said BBC correspondent Luisa Baldini.
The judge will have to decide whether the offences detailed warrant extradition.
But it would be up to Home Secretary David Blunkett to decide whether to order an extradition and Mr Hamza would then have the right of appeal.
Mr Hamza’s legal team are likely to argue for a delay.
They say they have been unable to appoint experts in the US to fight their case, because their client was named by President Bush in 2002 as a suspected terrorist.
The declaration placed restrictions on those who were allowed to assist him.
Mr Hamza, a former preacher at the Finsbury Park Mosque in north London, gained UK citizenship through marriage in 1981.