Eh... "empty streets".   I know very well they were closed off for security reasons; there have been complaints from Dublin shopkeepers on RTE about how much trade they'll have lost as a consequence. There were also rumours - not denied, as far as I'm aware - that armed British agents were also at hand (not unprecedented in Dublin...). While I wouldn't turn on my heel to see the Queen if she were at the end of the street, people can wave their wee flags if they want to, it's a harmless enough amusement. And, as Brendan Behan said, there are those in Ireland who would eat cooked Kenyan if they thought the Quality in England were doing it.