The Washington Post is live-blogging President Trump’s first official State of the Union address to Congress tonight. The speech begins at 9p.m. Eastern time and the president is expected to be, well, presidential.

Post national reporters Ashley Parker and Michael Scherer write that Trump aides say “he will deliver a unifying speech on American values and patriotism, one that touches on everything from the just-passed Republican tax plan and the new immigration proposal to trade, infrastructure and national security. The question is whether the swirl of conflict and diversion that has monopolized so much of his first year in office will distract from the message he is trying to deliver.”

The Post’s chief congressional scribe, Paul Kane, points out that it’s not just Trump whose behavior can be unpredictable — it’s also that of “mercurial” congressional Republicans when it comes to the president.

From Paul: “Sometimes they are in bitter fights with Trump, challenging his nationalist policy approach as an affront to traditional conservatism while also questioning his mental fitness for office. Other times they drift into a deep public swoon for the president that seems to directly contradict their previous criticism.”

Check back here for frequent updates on the speech, including real-time fact-checking and analysis of what the president says on key issues like the economy, national security and infrastructure.