As popular wisdom has it, the ideal embassy is a cross between an underground bunker and a marquee with a signpost saying 'Do come in and have a cup of tea'. As the two are incompatible, they tend to lurch between the extremes depending on the political climate in which they are conceived. A change in international relations can render them inappropriate overnight.
Eero Saarinen's American Embassy on London's Grosvenor Square is a classic case in point. Its glazed facade suggested an easy-going confidence during the Kennedy era, when members of the public were invited to use its library or to attend the jazz concerts, which were a regular event. When post-9/11 paranoia prompted a protective layer of riot barriers and armed officers, the expanse of exposed glass quickly came to signify vulnerability and fear.
The literal transparency of its architecture seemed to mock a local population forced to suffer the indignity of carrying ID at all times.
Given the regularity of attacks on its outposts, it is understandable that the US decrees that glazing should account for no more than 15 per cent of an embassy's walls. But it is to our own Foreign Office's credit that in commissioning buildings such as the Yemen Embassy, by Design Engine (see Building Study on pages 25-37), and Cullum and Nightingale's British High Commission in Kampala (AJ 11.05.06), it has sought a balance between accessibility and security, approachability and prestige.
George Gilbert Scott, architect of the Foreign Office's own Whitehall HQ, observed: 'If you look at a building and the windows are the right size, it may or may not be architecture. But if the windows are definitely too big or too small, you may be almost certain you are in the presence of architecture.' The Foreign Office has resisted such simplistic architectural statement. The transparency of its buildings is determined by function and comfort rather than political intent.