No one was accused of spying. The accusation was that 2 individuals, having refused to look at documents, heard "classified" information and passed it on to unauthorized individuals. To unauthorized individuals Israeli Embassy and to unauthorized individuals Washington Post. But only after their first call, to unauthorized individuals at the White House.
An interesting case, but the "rule" has to be applied equally, if it's to be applied at all, which will criminalize much of what goes on in the media and in government.
"will criminalize"? - or will hold to account for breaking the law and leaking classified info? Isn't it already a crime?
Lack of enforcement is not a good argument here, especially since it is very hard to prove that a citizen without a security clearance knew information was classified.