This is Dublin's Famine Monument, comemorating those who emigrated during the Famine (1845-50) Back then a series of poor harvests and inaction by those who could have prevented starvation (those who could have given aid didn't) led to a million deaths and a similar number emigrating. Starving immigrants were as unwelcome then as now.
In these enlightened times, little has changed.
It is easy to remember the events of the past, but we tend to ignore the problems of today, be it famine and destitution in other parts of the world,
The homeless people we step around every day as we go about our days.