he can be very emotional, act impulsively. in fact, some of the palace insiders say that he has a certain fondness for some of afghanistan's most profitable exports. >> nbc news chief foreign correspondent is kabul. do you hear reports that hamid karzai may be abusing drugs? >> his spokesman today flat li denied that allegation. there have been rumors to that effect here in kabul. but, no, i can't substantiate it. i've not seen any evidence to support that. >> galbraith goes on the record with some pretty explosive charges. not just the using afghanistan's most profitable export, but also that he's mercurial in nature. you never know which way the mood is shifting. what about that? can you concern that's a problem? >> reporter: that's certainly true. that is certainly true. that has been something that has been one of karzai's characteristics for years.