President-elect Donald Trump, who campaigned on a promise to rattle both the Washington establishment and the Republican Party, just picked a consummate GOP insider as his chief of staff.

That insider is Reince Priebus, a corporate lawyer who rose through the ranks of the Wisconsin Republican Party to become its national chairman ― and, over the course of the last year, emerged as a key Trump ally.

But Priebus’ impending move to the Trump White House was not the only major announcement of the day. The other was the appointment of Steve Bannon as chief strategist and senior counselor to the president.

Bannon is the controversial alt-right provocateur who used to run Breitbart News, the site known for trafficking in racist imagery and language. (He has himself been accused of flinging anti-Semitic comments, which he denied strongly). Bannon became chairman of Trump’s campaign in August, when it was struggling, and presided over it all the way through last week’s victory.

The decision to make Priebus chief of staff, traditionally the most important White House position except for the presidency itself, says a whole lot about the likely policy direction the administration will take. But Trump’s move to bring in Bannon as well signals tensions that could emerge over time ― or even quite soon.

Priebus and Bannon represent the two sides in the Republican Party civil war: its establishment and the angry, sometimes racist, movement trying to displace it.

Priebus will have at his disposal one of Washington’s biggest contact books and close ties with party leaders, as you’d expect from a national committee chairman. Priebus also has an intimate, insider’s knowledge of how Congress works ― and how to work Congress ― through the coordination of lobbyists and legislators.

But Bannon, a white nationalist and a political knife-fighter, is unlikely to defer to Priebus, notwithstanding who has the more important title. And Bannon has assets of his own. He will be able to exploit his ties to Breitbart and leaders in the far-right media, who proved themselves far more influential in the presidential campaign than anybody had imagined.

Sen. Harry Reid (D-Nev.) spokesman Adam Jentleson said Trump’s choice of Bannon “signals that White Supremacists will be represented at the highest levels in Trump’s White House. “

“It is easy to see why the KKK views Trump as their champion,” he added.

The Anti-Defamation League and Southern Poverty Law Center expressed concern over the appointment as well, with the ADL saying Bannon and “his alt-right are so hostile to core American values.”

Trump’s announcement about the positions actually listed Bannon first ― a sign, perhaps, of just how sensitive Trump and his team will be to perceptions that he’s cozying up to the establishment.

But it’s not hard to imagine disagreements erupting over issues where Trump and the establishment would be at odds. Those could lead to intense fights between Bannon and Priebus, playing out just steps away from the Oval Office.

Trade would be one possibility. Few issues were as central to Trump’s campaign. He promised to rewrite existing agreements and expressed skepticism of new ones. That call was particularly popular with white, working-class voters from communities that lost manufacturing jobs ― and who turned out for Trump at the polls last week.

But the GOP establishment, like its corporate backers, has long favored expanding trade with few restrictions. On Sunday, for example, House Speaker Paul Ryan (R-Wis.) dodged questions about differences he might have with Trump over trade.

Another issue could be Medicare, a program popular with Trump voters and one that Trump once vowed to protect. Ryan has also indicated that he intends to pursue Medicare privatization, a longtime goal.

But the conflicts could go beyond specific policy issues. They could include broader questions about messaging and strategy ― and they could get personal.

Priebus is close with Ryan, and the two come from the same state. Meanwhile, Bannon’s Breitbart has made Ryan public enemy number one for the angry wing of the party ― with the speaker as a stand-in for the kind of weak, middling leadership the alt-right blamed for the failure to repeal Obamacare or win the White House in 2012.

It’s worth remembering that official titles within the White House are not always indicative of power. Dick Cheney’s title was vice president, but so is Joe Biden’s, and the two had dramatically different levels of power in their respective White Houses.

And Trump will be turning to other advisers, too ― most influential among them, perhaps, is son-in-law Jared Kushner. Trump may trust him the most, because Kushner is family. But Kushner’s politics are something of a mystery and he has family and financial ties to Democrats in the New York-New Jersey area.

How this all translates to governing is anybody’s guess. Maybe even Trump’s.

This story has been updated with statements from Sen. Harry Reid (D-Nev.) spokesman Adam Jentleson, the Anti-Defamation League and the Southern Poverty Law Center.