As far as Belfast International Airport is concerned, Dublin is the wolf at the door.
And, up at Aldergrove, they're determined that this particular wolf doesn't force its way in.
As BIA's recently appointed managing director Graham Keddie tells this newspaper today, he suspects Dublin would love to put Ireland's second largest airport out of business.
Well, perhaps Mr Keddie and his staff should stay vigilant. Speculation is rife in business circles that Dublin Airport Authority (DAA) is considering making a bid for BIA's other significant rival, George Best Belfast City Airport.
It's understood DAA bigwigs were spotted wandering around the smaller airport recently - and they weren't there to welcome friends at the arrivals lounge.
Could such an audacious move be possible?
Belfast City is, officially, not for sale. But it has been making very marginal profits over the last few years. The latest accounts for Belfast City and its parent company ANKS Acquitions are for the year to December 2013; the former Harbour Airport made a profit of just over £1.2m.
The previous year, it posted a £644,000 loss and, until 2013, it had not made a seven-figure profit.
The parent company has been declaring even worse results and, consolidating the results for Belfast City and the financial company, pre-tax losses for 2010 to 2013 have been £21,616,000, £22,462,000, £27,079,000 and £6,671,000 respectively. Those figures look like an investment that has not performed as expected - and, suddenly, a cheeky bid for "The City" doesn't seem beyond the realms of possibility.
Mind you, if DAA did buy Belfast City, it would undoubtedly be to restructure the business; closure would not be on the table.
The outcome of airport's current planning application to remove the 'seats for sale' limit could tell a tale, so watch this space.