While the US legacy triumvirate have been making headlines about unfair competition from the Gulf carriers, Europe's leading airline group, IAG, has become part-owned by one of them.

And that deal, whereby Qatar Airways acquired an almost 10% stake, comes as IAG is locked in its own acquisition campaign in Dublin.

The events surrounding IAG over recent weeks underline its status as the leading legacy group in the European arena at the moment. Unlike its peers who are locked in battles to restructure their cost bases, IAG's management team is moving forward with the next phase of Willie Walsh's masterplan. Having got IAG's own house in order – or well on its way, at least – Walsh is now looking to his next opportunities.

The acquisition of Vueling two years ago added an important new string to IAG's bow. Vueling delivers a successful low-cost operation that can help drive the cost focus at the group's other airlines while spearheading short-haul growth.

IAG's challenge is to ensure that it doesn't screw Vueling up by interfering in what is a well-run business. But as far as IAG tampering with something that "ain't broke" goes, the signs so far are good.

"I don't feel restrained with anything. I don't think you would go to Vueling and find that there is something that we cannot do," chief executive Alex Cruz has told Airline Business.

IAG would do well to transmit that quote at full volume around Dublin, where Walsh recently gave a typically good account of himself in front of an Irish joint transport committee. He repeatedly assured politicians about Aer Lingus's slots, brand and management independence if it becomes part of IAG.

"Our intentions are completely positive," Walsh told the joint committee. "We believe we can bring to Aer Lingus the strength and support they cannot have as a standalone airline."

It is ironic that some question what sort of future Aer Lingus would face within IAG, when it could be argued that the Irish flag carrier's prospects might be less assured outside the group. A little more than a year ago, Walsh himself stated his support for Ryanair's takeover bid of Aer Lingus, arguing that it is "nonsense to have two domestic competing airlines in a market the size of Ireland".

As Walsh and his team wrestle with the Aer Lingus process, the Qatar Airways move has so far raised more questions than answers. In some respects the deal is no surprise: there is a strong personal relationship between Walsh and the Qatari flag carrier's boss Akbar Al Baker, with each often declaring respect for the other.

It was no coincidence that British Airways was Qatar Airways' "sponsor" when the latter joined the Oneworld alliance. The two airlines already have a cargo tie-up and have been working on a commercial partnership.

Qatar Airways has been on the IAG radar since before the group's creation. Back in 2010, the Doha-based airline was rumoured to be on the infamous "list" of potential partners drawn up by Walsh as he sketched out the future framework for the embryonic IAG.

After Qatar's last abortive foray into foreign carrier ownership (it briefly held 35% of Cargolux), it has so far played its cards close to its chest regarding the long-term thinking behind the IAG deal.

All Al Baker has said is that the transaction "represents an excellent opportunity to further develop our 'Westwards' strategy". Perhaps a reciprocal shareholding with IAG could be the next step, with Al Baker and Walsh sitting on each other's boards?

Whatever happens, the coming months promise to be compulsive viewing as events play out in Dublin, Doha and London, likely with long-term consequences for Europe's air transport business.

Source: Airline Business