Not so long ago, there was a time when the average American on the street was worried about the world’s population and how it was impacting the planet. But the span of just a few years, a variety of issues — from new economic thinking to charges of racism — emerged to make the topic issue non-grata.

Alison Stewart speaks with two journalists about where the population conversation stands today and what, if anything, we should be doing about it.

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Julia Whitty is an award-winning environmental reporter. As a correspondent for Mother Jones, she traveled to India to write about population growth – something she calls “the last taboo.” Julia’s latest book is “Deep Blue Home: An Intimate Ecology of Our Wild Ocean.”

Phillip Longman is a senior fellow with the New America Foundation and Washington Monthly. A former senior writer and deputy assistant managing editor at U.S. News and World Report, Longman’s byline has appeared in numerous magazines and newspapers. He is the author of “The Empty Cradle: How Falling Birthrates Threaten World Prosperity (And What to Do About It).”