It's disturbing because, if the UN is perceived as serving the purposes of a particular country, its credibility is weakened.
Impartiality is vital.
Such criticism was endemic during the cold-war. The situation in Iraq during the two years prior to last December's pullout of the UN Special Commission there came uncomfortably close to that description. Under Ekeus's successor, Australian Richard Butler, US intelligence reportedly used the UN weapons inspection team as a cover for installing a supersensitive listening device to intercept high-level Iraqi communications and beam them to a US satellite. Mr. Butler has firmly denied that his commission was ever engaged in spying. It's just that key data collected in that effort came through the application of US surveillance technology and went through US analysts.