I wonder if some of these foreign leaders make trips to the WH because they think it'll slow Trump down when he has to waste a day or two on them.
It does seem they built that tennis court to cover up their ritual space. They either did that as part of the general ongoing coverup which includes tunnels now being filled in, or they saw what was visible in public satellite images and did something about it.
The placement on the island must be significant for them to have been using that spot even though they had to go to the trouble of making a berm around it to conceal from the water.
Is there anything on the island that could be radar equipment? I expect they wouldn't have been too concerned about spy satellites or other kinds of govt reconnaissance because, as far as they were concerned, they owned the relevant governments. So the main threat is boats and low flying aircraft. Boats are harder to detect hence the berm.
I think I know what their excuse is going to be:
The berm is required to reduce crosswinds on the tennis court. It won't hold water though, because what the fuck was that arrangement with four directions in there beforehand?