WASHINGTON — A stroll around the South Lawn of the White House makes one thing instantly clear: UFC Freedom 250 on Sunday, celebrating the 250th anniversary of the United States and President Donald Trump’s birthday, will be unusual for everyone.The clashes are numerous and hard to ignore, with a TV-ready temporary live sports stage steps away from the back doorstep of the White House, looking like any other UFC octagon might when the promotion takes its traveling shows to arenas around the world.White House grounds have hosted concerts and Easter egg rolls, but never a live sports event, let alone an MMA cage-fighting spectacle. On the South Lawn sits a grandstand of about 4,300 seats, with one side backing against the small White House putting green. There’s the nine-story claw structure for lights and cameras, so imposing that it peeks over the top of the roof when viewing the White House from several blocks to the north. There’s the fan experience outside the South Lawn that would seem right at home hosting the NFL Draft or a music festival.There’s sponsor signage — plenty of it. Pretty much all the elements you’d expect from a pro sporting event, with the twist of plopping it right at the central symbol of power in the United States.Even for the worlds of sports and entertainment and politics, each of which craves attention and moves with no precedent, it’s clear that this presentation of seven fights intertwined with patriotic imagery will be something quite different from the status quo.The event, which has been in the works for more than a year, largely because of the friendship between Trump and UFC CEO Dana White, will feature seven fights before a limited crowd of VIP and military members, with tens of thousands more spectators expected to take in the scene on screens and with other performances at the nearby Ellipse.