Former President Barack Obama told Britain’s Prince Harry in a BBC 4 interview that hashtags alone do not bring about social change.

“One of things we want to do I think is as we’re working with young people to build up platforms for social change,” Obama told the British royal, who was guest editing the program. “Make sure that they don’t think that just sending out a hashtag in and of itself is bringing about change. It can be a powerful way to raise awareness but then you have to get on the ground and actually do something.”

The Obama administration was notorious for using hashtags in lieu of actual diplomacy or military action to address urgent problems.

The strategy reached its zenith (or nadir) in 2014, when First Lady Michelle Obama tweeted “#BringBackOurGirls” in response to the mass abduction of Nigerian schoolgirls by the terrorist group Boko Haram.

Our prayers are with the missing Nigerian girls and their families. It’s time to #BringBackOurGirls. -mo pic.twitter.com/glDKDotJRt — First Lady- Archived (@FLOTUS44) May 7, 2014

The same year, the State Department used the hashtag “#UnitedForUkraine” in the wake of Russia’s invasion of the Crimea in Ukraine.

To echo @BarackObama today-proud to stand #UnitedForUkraine World should stand together with one voice pic.twitter.com/VeMt578UdY — Heather Nauert (@statedeptspox) March 26, 2014

As spokesperson Marie Harf explained at the time, the “#UnitedForUkraine” campaign was launched as an expression of President Obama’s policy toward the crisis in Ukraine:

As part of our commitment to mobilizing the international community in support of Ukraine, we are coordinating with our partners and allies a global social media campaign with the hashtag #unitedforukraine. We are asking the world to show their support for Ukraine on social media by using the hashtag, as I just said, #unitedforukraine. Take action by sending U.S. officials and Department accounts tweets with pictures showing how committed we are to this. As the President said, no amount of propaganda can make right what the world knows is wrong. So our goal with this campaign and everything else we’re doing is to make sure the world knows what is happening, what is the truth, and making sure people come together again and are united for Ukraine.

The interview with Prince Harry was Obama’s first since leaving the Oval Office earlier this year. It took place against the backdrop of a controversy over whether President Donald Trump would be invited to Prince Harry’s wedding to American actress Meaghan Markle next year.

“All of us in leadership have to find ways in which we can recreate a common space on the internet,” Obama said — a remark that is being interpreted as an indirect slight to President Trump, though the context gave little indication that it was so.

Among the hard-hitting questions Prince Harry directed at Obama was: “Boxers or briefs?” He declined to answer.

Joel B. Pollak is Senior Editor-at-Large at Breitbart News. He was named one of the “most influential” people in news media in 2016. He is the co-author of How Trump Won: The Inside Story of a Revolution, is available from Regnery. Follow him on Twitter at @joelpollak.