Trump was correctly seen as the only threat to the deep state, so that is why he was targeted and still is.
I agree with all of that, but the question remains what was he targeted with? What was the motive for Mifsud to allegedly talk to Papadop about emails? I say allegedly because there may have been little or no mention of emails in March 2016. But sure the deep state was not planning an operation to culminate in a collusion investigation. That was possibly an insurance policy conceived in the last month or two of the election.
The question is what were they planning early on? An October surprise of Russia Trump collusion? They did that in spades and it was weak. They said Trump was hiding his tax returns because he was hiding Russian payments, and much more crap like that. And it all failed. A bunch of junk from FBI plants and informants would not have added much.