Without going into too much detail, Argentina barely have the operational capacity to deal with the land-based defences on the Falklands at this time, let alone the Naval capacity currently within operational distance of the Falklands.
They are nowhere near the capacity, operational readyness or relative modernity of the forces they had under the former Military Junta and the world itself is a different place, so any military action against the Falklands would be political suicide for Argentina on the international stage.
To answer your question directly, it would need some kind of operation to seize and hold the airfield, as well as disrupting communications long enough to ensure enough Argentine Forces are in place to counter the Royal Marines already on the Falklands and the JRRF who can be deployed to support the Falkland defence. The main issue with this is how do you get such a force capable of doing this onto the Falklands, with the advanced early warnong systems and Naval patrols it would be quite difficult for Argentine forces to land enough specialized troops to carry out such an operation and given the constant contact with a Type 45 Destroyer and a reported Trafalgar and Astute class submarines in the region, Argentina's mainland would be wide open for retaliation and they do not have sufficent defence capability to counter even one type 45 destroyer, let alone the Typhoons or Subs. The operational capability of both nations is vastly different today than in 1982, not to mention Argentine Forces are under equipped, do not have the combat experience of British troops, and lack the ability to conduct the kind of operations necessary to mitigate the effictiveness of the Falklands defences long enough to elimate the deployment of the JRRF or any retaliation on Aegentine Forces by the Naval presence already in the region.
unless they ship it all over to Blighty!!!
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