Proper size

The speck in front of the cloud, more or less vertically above the London Eye, is alleged to be Marine One with the President of the United States on board, as viewed from somewhere near Liverpool Street. Let's hope we can keep the speck speck-sized if and when it starts to meddle unhelpfully in our affairs.

But where are all the gunships from the various security outfits involved? Do they rely on top quality radar on the roof of the embassy to keep the skies otherwise empty in some exclusion zone? Is that what all the funny looking panelling is?