Assuming merely for the sake of argument the scenario presented by the Post is true, then the "classified information" he shared with the Russians was no longer classified, as he as president made a decision within his authority to declassify it.
The THIRD party that gave us that intelligence info. gave it to us on the speculation that it would NOT be shared with our arch enemy (sanctions against Putin's) Russia. Yet, Trump, to satisfy his fucked up ego, shared it anyway....
What are the chances that such a THIRD party will trust us again???