Re: Just a terrible idea
Most spies aren't the spies most people imagine spies to be. They are CAD draftsmen or scientists or engineers or visiting scholars or businessmen. You would, I suspect, be surprised at how many of those people get deported from countries all the time.
Visas expire because the project they were working on loses funding or they get misidentified as the perpetrator of a violent, but not deadly, crime. Previously undiscovered errors on visa applications suddenly come to light or they are implicated in misdeeds on the soil of an allied nation.
It doesn't really matter how they dress it up. Normal people are in one place today, gone to another place the next, because they are believed to be spies or patsies for spies.
There are rarely any repercussions, except an equal number of spies from your country will suffer one of the symptoms listed above and be sent home. Weapons tech will get people in real trouble, but if it's just good old fashioned industrial espionage everybody does their little dance and ship out the same number of different spies to the place that just booted them out.
Spying is a game all countries participate in. It's all quite formalized and (boringly) extremely not-Bond like.The prize for catching a spy is nothing, if you don't want to hand out prizes when your spies get caught (which is guaranteed to happen). In extreme cases, spying results in modifications to trade agreements and lowered interest rates from State sponsored banks. The Snowden case was fairly extreme, but now the trade arrangements have been made and it's all over. Situation normal, all fucked up.