Hard to plan for 'this is just generally suspicious'. But countries don't close themselves off for no reason. And they don't suddenly open themselves up. It could be a reaction to our appearance, as they imply, but given how little anyone at the Center knows about the Dream Width, for all we know, the Empire people knew this was going to occur.

[Or caused it.]

And if that's the case, that's a pretty strong lure for those of us more cautious than average.