Ok, it's in Dutch, but it's from a reliable source.
http://www.nos.nl/nosjournaal/artikelen/2006/1/9/090106_nl_afganistan.html
I suppose you could babelfish it, but I translated the most important parts.
[quote=Dutch News Article]
Pressure on the Netherlands to participate in the mission in South-Afghanistan is increasing. Apart from a call by NATO top man De Hoop-Scheffer, American Old-diplomat Paul Bremer III warned for sanctions in case the Netherlands would pull out.
(... Nato details ...)
If the Netherlands will not cooperate with the NATO-mission, it can expect American sanctions, says old-diplomat Paul Bremer III today in an interview with De Volkskrant. (One of the leading Dutch Newspapers)
"If the Dutch decide to not send any troops to Afghanistan, it will be detrimental for the Dutch interests in the United States", Bremer says in the interview. "The Dutch can't just say: okay, we're not going to Afghanistan, but everything stays the same. That's not going to happen."
According to the old-diplomat, the cancelling of the Afghanistan mission will in the long run lead to the American Congress taking decisions that will affect Dutch economic interests. "It's not hard to envision decisions being made that won't be in the interest of the Dutch."
Bremer understands that the Dutch politicians have their own considerations, but he points out the Americans do too. "In case of a negative decision, our politicians will ask themselves: What does this NATO stand for if allies are not willing to stand shoulder to shoulder with us? Especially Europe called for more international collaboration. Now that the opportunity arises, it is avoided."[/quote]
Note that this diplomat was part of a small delegation that was specifically visiting our country to discuss the matter. This threat (I think we may call it that) caused quite some uproar, because word had just gotten out about the secret CIA transports through Europe. Our government wanted to cancel the mission to Afghanistan to make the message clear to the Americans that human rights violations on European territory were not going to be tolerated. It caused such a huge debate that the Cabinet almost fell. A few weeks later the EU investigation into the secret CIA flights started and the Dutch cabinet all of a sudden decided to give the mission a go. We still don't really understand why.