Spirit Airlines is dead, but the finger-pointing is very much alive.Trump administration officials spent the weekend blaming former President Biden, whose Justice Department successfully blocked JetBlue from buying Spirit for $3.8 billion.Spirit told the White House to look in the mirror, saying its insolvency was sparked by an Iran war that's caused jet fuel prices to spike.Why it matters: Around 17,000 people just lost their jobs, and thousands of passengers found themselves stranded.It's also hard to guard against a future airline failure without a consensus diagnosis for the current one.Zoom in: Trump and Spirit both have legitimate arguments. It's just that they aren't mutually exclusive.Yes, DOJ's antitrust arguments now ring very hollow. It's hard to claim that keeping JetBlue and Spirit apart has preserved low-cost competition when Spirit planes are now parked like yellow school buses at midnight. It's also true that jet fuel prices were the straw that broke Spirit's back. Just last week, we wrote about how several European airlines may be at risk for the same reason.Yes, but: Even if you merge both narratives, there were other contributing factors.First, Spirit didn't sufficiently hedge its jet fuel costs. That speaks to poor management, or maybe to being overleveraged. After all, this was Spirit's second bankruptcy in less than a year — and it had been criticized during the JetBlue process for making decisions as if the merger was a fait accompli.Second, ongoing issues with Pratt & Whitney engines had caused Spirit to ground a bunch of its planes — creating significant losses, despite having reached a settlement.Third, Spirit bailed on a merger agreement with Frontier in order to pursue the JetBlue tie-up. It's possible that Biden's DOJ would have let Spirit merge with Frontier, which was significantly smaller than was JetBlue (which already had run into antitrust troubles on its planned partnership with American Airlines).The bottom line: It's impossible to know if a JetBlue-Spirit merger would have saved Spirit in the long term, or saddled the combined carrier with so much debt that it too would be liquidating as jet fuel prices climb.