Obama in 2011. (Pete Souza/Instagram)

For Pete Souza, who served as the chief White House photographer during former President Barack Obama’s eight years in office, every day is throwback Thursday — and, increasingly, an opportunity to slam President Trump.

Since Trump’s inauguration, Souza has been posting vintage images from Obama’s two terms on Instagram while subtly throwing barbs at the new commander in chief.

Last month, amid Trump’s war of words with Mexican President Enrique Peña Nieto over the president’s vow that Mexico will pay for his proposed wall along the U.S. southern border, Souza posted a photo of then-President Obama sampling tequila with Peña Nieto in 2013.

This one is for Grover. President Obama sampling some tequila with President Enrique Peña Nieto of Mexico in 2013. @heygrover A photo posted by Pete Souza (@petesouza) on Jan 31, 2017 at 6:18pm PST





Last week, after reports surfaced that Trump abruptly ended a tense phone call with Australian Prime Minister Malcolm Turnbull, Souza shared an image of a smiling Obama talking with Turnbull and former New Zealand Prime Minister John Key during the Association of Southeast Asian Nations summit in Laos in September.

Talking with then Prime Minister John Key of New Zealand, left, and Prime Minister Malcolm Turnbull of Australia last September at the ASEAN gala dinner. A photo posted by Pete Souza (@petesouza) on Feb 2, 2017 at 2:21pm PST





Souza then gave a direct shout-out to Bruce Springsteen, who apologized for Trump on behalf of America during a concert in Melbourne.





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During the chaos that followed Trump’s controversial executive order on immigration banning Syrian refugees, Souza responded by sharing an image of Obama and a young refugee.

Talking with a young refugee at a Dignity for Children Foundation classroom in 2015. A photo posted by Pete Souza (@petesouza) on Jan 29, 2017 at 5:16am PST





He followed that with a picture, taken in the Oval Office the day after the election, of Obama’s meeting with Alex, the 6-year-old boy who wrote a letter to the president about the heartbreaking image of a dust-covered Syrian boy in the ambulance that went viral last year.





It’s not just Trump who has drawn Souza’s ire. After Trump’s announcement of Neil Gorsuch as his nominee to fill the Supreme Court vacancy left by the February 2016 death of Justice Antonin Scalia, Souza posted a photo of Obama’s pick, Merrick Garland, who was blocked by congressional Republicans and never received a vote.

Merrick Garland. Just saying. A photo posted by Pete Souza (@petesouza) on Jan 31, 2017 at 5:28pm PST





On Monday, after a New York Times report that Trump aides have been forced to “confer in the dark because they cannot figure out how to operate the light switches in the Cabinet room,” Souza posted a photo of a fully lit Cabinet meeting.

Those damn lights A photo posted by Pete Souza (@petesouza) on Feb 6, 2017 at 7:33am PST





His caption: “Those damn lights ;)”

The same day, Souza shared an image of Obama meeting with three female advisers at the White House — a reference, perhaps, to Trump’s mostly male West Wing. Critics have noted that many of Trump’s photo ops are all-male affairs.

Meeting with top advisors. This is a full-frame picture. I guess you'd say I was trying to make a point. A photo posted by Pete Souza (@petesouza) on Feb 6, 2017 at 9:29am PST





Souza isn’t the only Obama alum using social media to take on Trump. An aggressive army of formerly buttoned-up Obama staffers have taken to Twitter to rail against Trump’s policies.

Related: Obama’s White House alumni fight Trump tweet for tweet

Souza’s trolling of Trump has gone beyond photo sharing too.

On Twitter, the former White House photog has been tweeting and retweeting links to articles critical of the Trump administration.

And on Wednesday, Souza retweeted a Trump message and compared his presidency to Netflix’s “House of Cards.”

Maybe the producers of House of Cards should think about a 13-part documentary on this POTUS instead of doing 13 new fictional episodes. https://t.co/3zmdSPLBMA — Pete Souza (@PeteSouza) February 8, 2017





I call my own shots, largely based on an accumulation of data, and everyone knows it. Some FAKE NEWS media, in order to marginalize, lies! — Donald J. Trump (@realDonaldTrump) February 6, 2017





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