How many Ambassadors to Brussels do we need?

In the news today was the story that Truman Hall, the residence of the Ambassador of the United States to the North Atlantic Treaty Organization (NATO), needed landscaping and a $700,000 budget was allocated for that purpose.

But it made me think - is this a different Ambassador than the one to Belgium?  Just for clarity, the US Permanent Representative to NATO is Ivo Daalder, and the official website is http://nato.usmission.gov/.   I can't find the address listed anywhere, but this is presumably for security purposes.

The US Ambassador to Belgium is Howard W. Gutman and their official website is:  http://belgium.usembassy.gov/.  Their address is Embassy of the United States of America, Regentlaan 27 Boulevard du Régent, B-1000 Brussels, Belgium.

The US Ambassador to the European Union is William Kennard and his official website is: http://useu.usmission.gov/.  Their address is Rue Zinnerstraat 13, B-1000 Brussels, Belgium.

And of course, these are separate from the US Ambassador to the Netherlands, (position empty since Sept. 2011), with website http://thehague.usembassy.gov/, and the Ambassador to Luxembourg, Robert A Mandell, website: http://luxembourg.usembassy.gov/.  And the US Ambassador - Robert Mikulak - to the Organisation for the Prohibition of Chemical Weapons (OPCW) in The Hague, Netherlands.

So these aren't all in Brussels, but that is 6 in a very small area.  Can't any of these be combined?  Well, maybe that is why a new ambassador to the Netherlands hasn't been appointed yet.

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The intended ambassador to the Netherlands, Timothy Broas, was removed from consideration for the apppointment in July 2012 after he got a DUI.  Why hasn't anyone else been nominated?  Well, you have to raise $500,000 to get the seat and no one else cares that much to do it.

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Update: June 23, 2013.  Ambassador Howard Gutman allegedly solicited underage prostitutes, so he will be replaced by Denise Bauer.  Her only qualification was that she raised $500,000 for Obama's re-election in 2012.  What a joke.