Beginning on July 29, commercial airline traffic to the US from Shannon airport in Ireland will have the advantage of full preclearance.  That means that all US customs, immigration and agricultural clearances will be completed before the passengers leave Shannon.  And that, in turn, means that commercial traffic leaving Shannon can go to any airport in the US (at least any airport within range of the aircraft and big enough to handle its arrival).  No longer will passengers have to arrive at an American international airport, clear customs, and then make their onward domestic connections.

Better still, beginning in October 2009 the same preclearance service will be available for general aviation aircraft (smaller, non-commercial planes).  After clearing immigration and customs in Shannon, these planes will be allowed to fly direct to any general aviation airport in the US.

This is a win-win-win for everyone.  Passengers get convenience – they can make their travel plans direct from Shannon (or Dublin when the preclearance facilities open there in 2010) without any need to change planes at a busy US airport.

Shannon wins too – having a preclearance facility will attract traffic through the airport, and help build the economy in western Ireland.

And the US wins as well – preclearance of passengers overseas will help keep problems overseas.  Contraband and illegal goods will be interdicted before leaving Ireland.  Passengers who are not admissible to the US will be turned around and sent home before they depart, instead of making the sad return trip from the US.  Sophisticated radiological screening systems will help keep weapons of mass destruction off shore.

All of this will be a great boon to trade, to tourism, and to security.  Who could ask for anything more?  It isn’t often that a government policy makes this much sense.

Paul Rosenzweig, the founder of Red Branch Consulting, PLLC, formerly served as Deputy Assistant Secretary for Policy and Acting Assistant Secretary for International Affairs at the Department of Homeland Security.