I don't understand the "he conned us" stance. He was literally saying all these things before getting elected. He wasn't being coy about it, we all knew it would be terrible, and here we are. What was the con exactly?

If there's one thing you can't accuse Trump of, it's ever masking how utterly nonsensical he is.

Saying “he conned us” is easier for people to accept than being introspective, taking responsibility and experiencing ego dissolution.

Grump said all of these things before getting elected, but he also said their exact opposites as well. That he can say blatant lies while having a "charisma" such that people hear what they want to hear is exactly how a con man operates. Hence, they were conned.

However, the responsibility still arises as half of their fellow citizens were telling them that they were being conned. But rather than listening to the critics they actively remained ignorant while gloating about "liberal tears" and so on.

i thought he was more anti-war

Don't know why you're getting downvoted, but I believe the con was the "no wars" line. He was supposed to stop the Ukraine war in 24 hours, remember but he seemed to just lose interest in it.