nosuchreality said:the big Ifs are
if the information is from foreign government operations
if she is actually a government operative
if she actually provides information
if the campaign then doesn't turn it over or file appropriate forms
if...
Did you read the Email?
"The Crown prosecutor of Russia met with his father Aras this morning and in their meeting offered to provide the Trump campaign with some official documents and information that would incriminate Hillary and her dealings with Russia and would be very useful to your father."
"This is obviously very high level and sensitive information but is part of Russia and its government?s support for Mr. Trump"
"I can also send this info to your father via Rhona, but it is ultra sensitive so wanted to send to you first."
Actually providing information doesn't matter the same way as it doesn't matter whether you succeed if you try to murder someone. The sole promise of Russian documents and information is what hooked Jr. in. He didn't shrug it off but rather embraced the possibility of getting a hold on that material and ended up setting up and going to that meeting.