US airlines must be suckers for punishment. Why else would Delta and American Airlines be jostling to throw money at the perennial problem that is Japan Airlines? The Japanese carrier, Asia's largest by revenues, has yet to shed legacy costs built up over decades – something the US industry only achieved through bankruptcy, violent reorganisation and government assistance. It is unclear that the political will to push through change exists (a committee is appointing a second one to come up with proposals). Japan Airlines is also struggling under Y912bn ($10bn) of net debt and still losing money.

However, with international mergers still mostly illegal, joint ventures are the likely route to future co-operation – an approach that is helping to cut costs for Delta, Northwest and Air France-KLM over the Atlantic. So Delta's proposal that JAL switches from the OneWorld alliance to its own SkyTeam alliance, in return for $500m of non-voting equity finance, $200m of debt and a $300m revenue guarantee would be a step towards that goal. It also makes life difficult for weaker competitor American Airlines, which has little Asian exposure and must try to fund a counter-offer to JAL.

Anti-trust objections to Delta/JAL co-operation may be surmountable. Combined, the two would have 51 per cent of slots at Tokyo's Narita airport, less than American Airlines and British Airways would control at Heathrow if their application for anti-trust immunity were approved. Yet the US carriers are living on borrowed time, with debt and equity raisings providing only limited breathing room. Structural issues remain unaddressed, such as the overabundance of hub airports with too few spokes. And JAL needs far more cash than its peers could supply. Global tie-ups are the future, but should not distract from self-preservation.