Shared ground
This passage presents Jehoram’s reign as a period of political loss for Judah. Edom successfully throws off Judah’s control, sets up its own king, and stays independent “to this day” (from the narrator’s later viewpoint). Libnah’s revolt at the same time adds to the picture of weakening authority.
The text also shows the writer’s typical way of summarizing a king: a key event or two, a brief note that more records exist elsewhere, then death, burial, and succession. Jehoram’s response (a rapid campaign with chariots and a night attack) is reported, but the final outcome emphasized is not recovery—it is continued revolt.
Where interpretation differs
1) What happened in the night engagement (v. 21). Some read the night strike as a limited tactical success (Jehoram breaks through an encirclement). Others read it as an overall failed campaign (even if Jehoram fought his way out, Judah still retreats and loses control).
2) Who “the people” are who “fled to their tents” (v. 21). Some take “the people” as Judah’s forces (they give up and go home). Others take it as Edom’s forces (they scatter after being struck), though the broader paragraph still ends with Edom independent.
Why the disagreement exists
The Hebrew wording in v. 21 can be read in more than one way about who is fleeing and how to connect that sentence to the long-term outcome in v. 22. Also, the writer is not trying to give a full battle report; the narrative is compressed, so readers have to infer more than the text states explicitly.
What this passage clearly contributes
Explicitly, the text claims: (1) Edom revolted during Jehoram’s reign, (2) Edom installed its own king, (3) Jehoram responded militarily with chariots and a night strike, (4) after the clash someone flees “to their tents,” and (5) Edom’s independence remained in place “to this day.” Theologically (by inference from the book’s pattern), Kings is presenting national and leadership history as meaningful: territorial losses and internal instability are not treated as random footnotes but as defining features of a reign within Judah’s larger story (compare the broader narrative framing in 2 Kings 8:16–8:19).