If indicted, would any jury convict? (given how polarized society is, someone on the jury would be a Trump fan, unable to convict, regardless of the evidence)
If not convicted, then he would be free to use that as vindication and fuel for his next campaign.
(IF doomed to fail, and given the consequences of failure, then why indict, especially given the precedent and claims of political bias that would result, not to mention the potential calls for impeaching and seeking wrong doings from the next batch of political leaders/candidates).
IS the cost more than the potential gain?