The only way Sessions could have ever hoped to preserve his political career was simply to never abandon his Senate seat. By accepting the AG appointment, he was inevitably going to find himself in a position where he’d either incur Trump’s ire for refusing to take a bullet or taking that bullet and exposing himself to criminal liability. Even if he’d chosen not to recuse himself after Comey’s termination and put the kibosh on any investigation by the DOJ, all he would have done is delayed the inevitable unless one assumes that the House would have stayed in Repub hands past the midterms. If anything, a total refusal by the DOJ to look into any of Trump’s crimes with Sessions in the AG office would have only fueled the fires that saw a Blue Wave in 2018.