If DCA's runways could support it, what international destination do we think would be interesting picks? Maybe DUB because preclearance? 757s already regularly operate to/from DCA; surely a lightly loaded 321LR/XLR or 220 could do the same across the water?

Or if we pretended DCA had CBP facilities... maybe LHR or ORY would have sufficient demand for a daily flight. Maybe it'd have to be all business like the 318s BA used to operate from LCY.

N.b. This is a mere thought experiment, in a thread about beyond-perimeter flights.