The US is to build the world's most expensive embassy, in London. Described as super-high-tech, one of its main defences against terrorism is a moat.
"The expressive challenge is to give form to the core beliefs of our democracy – transparency, openness, and equality," say its designers, which is presumably why they've made it as hard to get into as possible.
They also want to signify "solidity, strength and permanence", so they're building it out of glass. The present embassy needs to be torn down, apparently, because after 50 years it's "showing signs of wear and tear".
This could put a few noses out of joint in Britain, where we're still staggering on with public buildings up to 900 years old.
But the building's green credentials are impressive (the architects don't suggest that this is a core belief of the US). It's designed to be carbon neutral, with a self-sufficient water system.
The roof will be covered with a crystalline photovoltaic array, while the walls will be sheathed in ethylene-tetrafluoroethylene to shade the interior and capture more solar power.
There's a biomass-based heating and power system, along with occupancy sensors and LED lighting to reduce power consumption; the biolding is forecast to be a net exporter of energy when it opens.
"The KieranTimberlake Team's concept holds great potential to be an iconic Embassy building," says acting director of the Bureau of Overseas Buildings Operations, Adam E Namm.
"Significantly, the design concept boldly incorporates sustainability features, especially important as the US Government, as other countries and businesses, seeks to go green."
Work should start in 2013, and be completed four years later. "Although this is a big step forward, we still have a lot of work to do. In many ways, this is just the beginning," says ambassador Louis B Susman. "KieranTimberlake's design concept will evolve and develop as we move forward with the consultation and planning process."
And if complaints over the high cost of the building - rumoured to be over $1 billion - cause designer James Timberlake any problems in future, he's clearly got an alternative career ahead of him as a writer.
"The design seeks a holistic fusion of urbanism, building and landscape," he says. "Our goal is that the New Embassy is both evocative and performative."