WASHINGTON >> Donald Trump took the oath of office on Monday inside a tightly packed Capitol Rotunda, where he was surrounded by a very different Washington than he was eight years ago.

Then, when Trump gave a speech about “American carnage” on the inaugural stage in the rain, many congressional Republicans were silently prepared to push back on the most radical elements of his agenda and investigate his background.

Today, they are almost unanimously backing the president. World leaders and corporate CEOs who once balked at Trump were scheduled to attend the ceremony, prepared to brave the bitter cold to publicly show their support before events were moved inside.

It is also a far different Washington from four years ago, when the stage built for Democrat Joe Biden’s inauguration had to be hastily repaired after an insurrection of Trump’s supporters just two weeks beforehand. The rioters tore pieces off the scaffolding to use as weapons against police who tried to stop them from breaking into the Capitol and halting the certification of Biden’s victory.

The Rotunda was packed then, too, as rioters violently rushed in after breaking through the main doors. They hung off statues, called out for lawmakers and battled police who were trying to push them out of the building.

Trump refused to attend Biden’s inauguration, and many Republicans thought his political career was over. But he came back stronger than ever — and brought Washington with him.

Trump’s second inauguration was also different because it was held indoors, a last-minute change because of the frigid, windy weather. The platform on the West Front of the Capitol, built over many months, will stand unused and barren as he takes the oath inside.

South Dakota Sen. Mike Rounds says that while Trump was an unknown in 2017, Washington Republicans now understand how he operates.

“They know he’s going to make statements and that he’s going to test the waters,” Rounds says. “But they also know that when it’s all said and done, he’ll take counsel and then he’ll make a decision.”

Despite the widespread support and unified power in Washington, Trump’s second presidency still faces obstacles — including a narrow majority in the House and different views within the party as he and Republican leaders eye massive bills to cut taxes, secure the border, deport immigrants and boost energy production.

An early test in December showed Trump’s limits after Congress rejected his push to add a debt limit increase to year-end spending legislation.