Quizmonster,
The US administration doesn't tend to ask, it just gets.
Have you been paying attention to recent events and possible clandestine arrangements between the UK and US governments?
Do the names Sowden and Miranda register with you?
Whilst I agree that Assange should face a Swedish court, if there isn't a problem then why can't he get assurance that he won't be the subject of rendition to the US?
Maybe this might explain his stance for you a little better:
Current and former US government officials have accused Assange of terrorism. When asked if he saw Assange more as a high-tech terrorist or as a whistleblower, like those who released the Pentagon papers in the 1970s, US Vice President Joe Biden said: "I would argue it is closer to being a high-tech terrorist than the Pentagon papers."[186] In May 2010, Senate Minority Leader Mitch McConnell had used the phrase, calling Assange "a high-tech terrorist", and saying "he has done enormous damage to our country. I think he needs to be prosecuted to the fullest extent of the law".[187] Also in May 2010, former House Speaker Newt Gingrich said: "Information terrorism, which leads to people getting killed, is terrorism, and Julian Assange is engaged in terrorism. He should be treated as an enemy combatant."[188]
In July 2010, after WikiLeaks released classified documents related to the war in Afghanistan, Chairman of the US Joint Chiefs of Staff, Mike Mullen, said at a Pentagon news conference, "Disagree with the war all you want, take issue with the policy, challenge me or our ground commanders on the decisions we make to accomplish the mission we've been given, but don't put those who willingly go into harm's way even further in harm's way just to satisfy your need to make a point. Mr. Assange can say whatever he likes about the greater good he thinks he and his source are doing, but the truth is, they might already have on their hands the blood of some young soldier or that of an Afghan family." Assange responded later in an interview by saying, "There is, as far as we can tell, no incident of that. So it is a speculative charge. Of course, we are treating any possible revelation of the names of innocents seriously. That is why we held back 15,000 of these documents, to review that". Assange also claimed it was 'ironic' of US officials and military leaders to accuse him of having blood on his hands.[189]
On 30 November 2010, former Vice-Presidential candidate Sarah Palin called for Assange to be pursued "with the same urgency we pursue al-Qaeda and Taliban leaders".
If I were him, I'd be VERY fearful of the possibility of rendition!