The Celtic Tiger is still a sick kitty. Ireland’s economic takeoff, which began accelerating in the 1980s, spun out of control early in the new millennium and was crashing even before the near-meltdown of the global financial system in 2008.

Back in the late purple stage of the property boom, a nation besotted with an insanely over-confident real estate market seemed willing, even eager, to finally forget its own history of subjugation, oppression, theft, poverty, famine and emigration. Who had time to brood over the Potato Famine when the aged parents’ wee house happened to be worth four times what it was five years ago?

Those days are gone. And these days, as Tim Pat Coogan writes in The Famine Plot, “Poverty and emigration have remained continuing themes in Ireland,” and the country has been learning all over again that “its defenses were too fragile to cope with the longstanding Irish vices such as clientalism and corruption.” What Coogan suggests — and this is just one of many intriguing points made in his book — is a linkage between the recent Irish collapse, Irish feelings of helplessness and that demographic and moral disaster of the Irish 1840s: the Potato Famine, otherwise known as The Great Hunger.

What happened in the 1840s in Ireland, and why, and who was responsible, is also the subject of John Kelly’s cogent and forceful popular history, The Graves Are Walking. Kelly and Coogan have written polemics against the British government of the day and its inadequate response to Ireland’s nightmare. They sustain their arguments with sound materials. Kelly, an American, is cool and prosecutorial in tone. He has the facts, ma’am, and his book is an accessible, engrossing history of horror. Coogan, the Irish author of controversial popular biographies of Michael Collins and Eamon de Valera, as well as a history of the IRA, is fiercer and angrier. He sounds like the witness who actually saw the crime.

The Irish potato crop failed during a series of seasons in the 1840s. By 1851, Coogan writes, “the population of the country had been reduced by death and emigration from 8,175,000 to 6,552,000.” The country was changed. The changes were deep and sustained, and are felt to this day. Ireland’s population is smaller now than it was in 1845.

A fungus, phytophthora infestans, ravaged the Irish potato crop. But potato crops were infected elsewhere in northwest Europe during that decade. There was phytophthora infestans, but no famine, in Belgium, France, Scotland. Why did Ireland starve, while Belgium did not?

Coogan’s pages spark and sputter with a deep, lingering, well-cherished rage at the British government and laissez-faire attitudes and policies adopted by Prime Minister Lord John Russell and civil servant Sir Charles Trevelyan. British reluctance to interfere with the supposed workings of the free market economy allowed famine to continue in Ireland at a time when the country was producing and exporting tons of food to England.

Ireland’s history as a conquered nation shaped a disastrous system of land tenure, which resulted eventually in a large population dependent on a single crop. These were the conditions that turned crop failure into famine. But for many in London, it was the feckless Irish — especially the proliferating, starving cottier class, crowded onto the most marginal lands in southwest Ireland — who were the core of the problem.