Last week, I explained how the Trump administration could exceed my expectations and asked Donald Trump supporters to lay down their own markers. What would it take for them to change their minds and stop supporting the president? The first batch of responses included two emails that stood out as particularly useful. Together, they illustrate political challenges that Trump will face as he tries to hold on to the very different sorts of supporters who form his coalition.

Brendan, an immigration hawk from Colorado, represents one part of Trump’s base:

I am a first time voter, 19, and Trump would have to back down on his campaign promises for me to not support him. I am already a bit nervous about some of his cabinet appointments, such as the Goldman Sachs bankers and the establishment neoconservatives like John Bolton he has chosen. I feel like the wall, and his strong anti-illegal immigration stance, are his signature policy proposals, and he would have to cave to pressure from establishment anti-Trump Republicans and betray his immigration policies he laid out in his AZ speech. His anti-globalization policies and ideas are very important to my family and I as well. Finally, and perhaps most importantly, he has to appoint conservative, Scalia-style SCOTUS judges. Really, for me it comes down to the immigration, trade, and SCOTUS issues. If he betrays any of those, or otherwise starts acting like another Bush or like Marco Rubio, or John McCain, or Lindsey Graham, I'll feel betrayed. Trump can tweet as much as he wants though … to me it's hilarious, even if not exactly presidential. You probably think the things I support about Trump are the worst things about him, but that's exactly why most of my conservative family and I support him (I'm not popular in college). Since Reagan (and not even Reagan, to be honest), we haven't had a GOP President actually follow through with conservative/right-wing ideas that the base actually wants. The GOP base, and myself, never wanted “immigration reform,” we wanted less immigration, and not a hint of amnesty. We've never been for unlimited free trade, but for some reason politicians have always considered it sacred. I don't want compromise anymore, I want to win! Anyways, I just wanted to say what I think Trump's core supporters, from the very beginning, will want Trump to do … it probably isn't what the 'moderates', RINOs and liberals want … sorry.

Among other things, Brendan’s email is a reminder that intra-Republican fault lines remain with us. (He’s mistaken, though, to say that Trump has named Bolton to a position in his administration.) Yes, Trump prevailed over Jeb Bush, Marco Rubio, Ted Cruz, John Kasich, and Lindsey Graham in primaries. At the same time, he lost the popular vote and enters office with a historically low approval rating, while those rivals are or were popular elected officials in Florida, Texas, Ohio, and South Carolina. Figures like them are sprinkled throughout the Republican Senate. (John McCain is 80 and just won a six-year term. Surely Trump can’t threaten him.)