Donald Trump used his inaugural address to repeatedly attack the policies of one of his predecessors. His primary target wasn’t Barack Obama, though. It was George W. Bush.

Trump didn’t mention Obamacare, the Iranian nuclear deal, the opening to Cuba, or any of Obama’s other signature accomplishments.

Instead, from trade to immigration to the long wars in Afghanistan and Iraq, Trump took direct aim at the policies of the most recent GOP president. Trump didn’t mention Bush by name, but he didn’t have to: The message — that he represented a very, very different kind of Republican than Bush — came through clearly all the same.

Take Trump’s comments about how the US had wrongly “spent trillions of dollars overseas while America's infrastructure has fallen into disrepair and decay.” The president who launched those costly wars — and who was responsible for the bulk of the estimated $5 trillion that the US has spent in Iraq and Afghanistan, and the bulk of the 8,000 American military deaths in the two countries — was Bush, not Obama.

Trump campaigned on a promise to dismantle Obama’s legacy, beginning with the president’s signature health care initiative, and he may yet do so. But on the biggest day of his life — and speaking to an audience of hundreds of millions of people inside and outside the US — Trump didn’t sound like a Republican taking aim at a Democratic predecessor. He sounded like a Republican taking aim at a Republican one.

The two most recent Republican presidents seem to come from different planets

Trump and Bush couldn’t be more different as people. Bush was the son of a president, the grandson of a prominent senator, and the brother of a popular governor; Trump is the son of a real estate tycoon who never sought or held elected office.

During the 2016 campaign, Bush campaigned for his brother Jeb, and then refused to endorse Trump once the self-proclaimed businessman won the nomination. Neither he nor his father, former President George H.W. Bush, voted for Trump last November.

Those differences extend to the policy level. Bush ran as a “compassionate conservative” and staunch advocate of free trade. He used his 2007 State of the Union address to call for comprehensive immigration reform that would give undocumented immigrants a pathway to citizenship and argue that it was “neither wise nor realistic to round up and deport millions of illegal immigrants.”

Bush oversaw a massive expansion of Medicare that specifically barred the federal government from negotiating for lower drug prices. He prided himself on speaking basic Spanish, and worked to build a relationship with then-Mexican President Vicente Fox.

Trump, by sharp contrast, campaigned as an economic nationalist and channeled the anger of white working-class voters who felt left behind in a changing America. He opposed any sort of immigration reform and said he would deport up to 11 million undocumented workers and build an impenetrable wall along America’s border with Mexico to keep more from coming in.

Trump has specifically called for allowing Medicare to negotiate drug prices and use its enormous purchasing might to try to bring costs down. He also used an early debate to argue that the US was a country “where we speak English, not Spanish,” and has waged a long and vulgar Twitter war with Fox.

All of that, though, pales in comparison with how differently Trump and Bush view foreign policy — and how differently they talk about it.

Bush wanted to maintain the existing world order. Trump wants to undo it.

Bush was a neoconservative who believed the US could and should use its military, economic, and political muscle to prod dictatorships and authoritarian states toward democracy. He put those beliefs into practice most notably in Iraq and Afghanistan, where the US quickly deposed the country’s rulers only to spend enormous amounts of blood and treasure on a seemingly endless effort to rebuild their physical infrastructure and political systems.

Trump, in another sharp contrast, spent his entire campaign decrying the two wars as catastrophic mistakes that wasted American lives and resources while doing nothing to keep the US safe. He has cozied up to Russian strongman Vladimir Putin and spoken admiringly of Saddam Hussein, the Iraqi dictator Bush literally went to war to depose. Trump also stirred outrage during the Republican primary fight by belittling Bush’s record on terrorism and blaming him for not stopping the 9/11 attacks.

All of which brings us back to Trump’s inaugural speech and the three implicit, but clear, shots it took at Bush:

The US, Trump said, had for too long “subsidized the armies of other countries while allowing for the sad depletion of our own” and “spent trillions of dollars overseas.” Both of those lines were implicit critiques of Bush, who spent tens of billions of dollars to build an Afghan national army and rebuild Iraq’s war-shattered military and then many hundreds of millions more to support American war and reconstruction efforts in the two countries.

Next, Trump said that “every decision on trade, on immigration, on foreign affairs will be made to benefit American workers and American families,” adding that his administration would work to “protect our borders from the ravages of other countries making our products, stealing our companies, and destroying our jobs.” Bush’s official White House website, by contrast, bragged about the 11 bilateral trade deals he signed while in office as well as a broader agreement with the Dominican Republic and Central America.

Finally, Trump mentioned strengthening America’s borders three times in his speech — more than he mentioned taxes, crime, or other typical Republican go-to phrases. This, paired with Trump’s constant talk during the campaign about deporting millions of undocumented immigrants, sounds like yet another critique of Bush’s willingness to find ways of bringing those workers and families out of the shadows rather than tracking them down and kicking them out of the country.

Donald Trump won the White House by campaigning as a different kind of Republican, one who espoused a neo-isolationist foreign policy paired with harsh anti-immigrant rhetoric and skepticism of — if not outright opposition to — free trade deals. Trump’s presidency is just beginning, and it’s far too soon to know what actual policies he’ll put in place. One thing is clear, though: If his inaugural speech is any guide, Trump will repudiate the policies of his last Republican predecessor at least as strongly as that of his last Democratic one.