Many Irish who returned home to prosper in the Celtic Tiger have been left high and dry.

Thousands left America when the going was good. Many splashed out big money for overpriced houses and waited for the boom to continue.

It didn't.

Now many are desperate to return but have given up their green cards or were undocumented in the U.S. to begin with.

But no Irish need apply.

Lorraine O'Kane, who moved to the United States from her native Northern Ireland and was soon successful in the banking business got a green card.

When the going was good in Ireland she decided to return home but now calls it among the greatest mistakes of her life.

She'd love to return, she told the Philadelphia Inquirer newspaper from her home outside Belfast. But that now looks impossible.

Her green card is now "abandoned" say immigration officials because she has lived outside the US for one year.

"I always did like America," she told the newspaper. "It was a stupid decision to leave."

That is now a common lament. Siobhan Lyons is executive director of the Irish Immigration Center in Upper Darby, Philadelphia .

"Since summer," she said, "I have had about 25 calls from people who had green cards, went home to Ireland, want to come back, but can't."

Lyons says overall she has received 100 calls from people in Ireland desperate to come to the U.S. It is a theme repeated across every major Irish American town from New York to California.

Alas, it is very difficult to come here legally and those that returned home in the good times mostly gave up their green cards.

Such is the state of Ireland in 2011 that were the gates to open again to America the flood would never stop from the Emerald Isle.

And that's a sad reflection.