President Trump's threat to move this year's Republican National Convention out of Charlotte, N.C., in the midst of a global pandemic has those who organized previous conventions scratching their heads over just how the GOP would overcome the almost insurmountable logistical hurdles of throwing together one of the biggest events on the quadrennial calendar in just two months.

In a tweet Tuesday, Trump said North Carolina Gov. Roy Cooper's (D) restrictions on the number of people who could participate in the convention meant Republicans "are now forced to seek another State to host the 2020 Republican National Convention."

Trump and the Republican National Committee (RNC) have deployed site selection teams to several cities that might serve as alternate sites for the president's renomination, including Jacksonville, Fla., Nashville, Tenn., Dallas, Phoenix, New Orleans and Savannah, Ga.

But veterans of conventions past say it is almost certain that Republicans will have to keep the bulk of their convention activities in the Queen City. Even before the logistical nightmare that would be setting up an entirely new convention in just two months, the party has already sunk millions of dollars into building the infrastructure necessary to run a modern convention and committed to spending millions more through contracts that cannot be broken.

"The RNC’s Executive Committee has voted unanimously to allow the official business of the national convention to continue in Charlotte. Many other cities are eager to host the president’s acceptance of the nomination, and we are currently in talks with several of them to host that celebration," Michael Ahrens, the RNC's communications director, said in a statement.

An RNC spokesperson said the party is confident it could set up a convention in just two months.

"We have a highly skilled team and many states are eager for the revenue and economic advantages that this celebration will bring," the spokesperson said in an email.

But organizing a political convention is a massive undertaking, one that takes two years or more and costs tens of millions of dollars. The logistics range from the mundane task of assigning delegations to specific hotels and then organizing bus routes that can deliver them to an arena to the physical design and construction of platforms, stages and sight lines that will deliver the best optics for what is in effect a four-day infomercial for a political party's nominee and its rising stars.

"All of these just take an enormous amount of planning and community bandwidth. It is every bit of the full two years of planning," said David Gilbert, who ran Cleveland's host committee in the run-up to the 2016 convention where Trump was nominated. "It's one of the largest events that takes place every four years in the country in terms of numbers of people, and it probably is the most intricate when it comes to security planning."

Behind the scenes, the Secret Service long ago deployed a special team to a host site to coordinate with local and state law enforcement, and Congress appropriates tens of millions of dollars to ensure the safety of delegates, party leaders, volunteers and the protesters who are sure to show up.

"Let’s be clear: It is simply not feasible to replicate the efforts needed, in a new city and in just two months' time, to put on a convention that would look or feel in any way similar to today’s modern nominating meetings," said Clark Jennings, who directed operations at the 2012 Democratic convention.

"Producing these complex events requires an enormous scale of sophisticated planning and intergovernmental coordination, the buildout of niche infrastructure within the convention hall and across the host city, and the negotiation of hundreds, if not thousands, of contracts to provide housing and transportation, alone, for the tens of thousands of delegates, elected officials, media, supporting staff and volunteers that descend on a convention city," he added.

Then there is the matter of the 15,000 members of the media who descend on a convention city. Those reporters, producers and anchors require the space to report and file their stories, the camera angles to capture the action and, in some cases, the VIP facilities, some custom-built, to woo potential advertisers and elected officials coming in for interviews.

A senior staffer at the 2012 Republican convention recalled having to move a television network's camera two days before the convention began, a seemingly simple task that became a substantial headache.

"The retrofitting of the arena, alone, to turn it into the equivalent of a custom-designed combination movie set, media and communications studio, [and] political rally takes many months. The amount of fiber-optic cabling that gets installed into a convention arena is extraordinary and takes significant time," Jennings said. "Rome wasn’t built in a day; neither can a convention hall in 2020."

Several veterans of recent conventions said organizers now have to factor in a significant new challenge: accommodating the monumental internet bandwidth required not just to allow the media to broadcast the speeches and hoopla but also to let delegates and visitors broadcast through their own social media channels.

While no one was tweeting or Instagramming the 2000 or 2004 convention, every moment of this year's events will be captured and broadcast on smartphones and tablets.

"The amount of news that came out through social channels compared to four years before was significantly exponential, and I'm sure now in 2020 it's exponentially ahead of what it was in 2016," Gilbert said. "You can't afford [Wi-Fi networks] to go down."

A Republican familiar with the Trump campaign said they have trouble with bandwidth at the Make America Great Again rallies that have become Trump's signature.

Organizing committees in Charlotte as well as Milwaukee, which plans to host the Democratic National Convention in mid-August, have spent two years or more raising money from the local business community and recruiting volunteers who will make the buses run on time. Duplicating those efforts in the space of a few months seems equally difficult.

The benefits to a host city are substantial, both in economic activity and in the coverage they get from reporters looking for stories outside the arena where the festivities take place. Gilbert said Cleveland estimated it received $180 million in economic activity during the convention week in 2016 and from a residual glow of positive news coverage for the city itself.

"We benefited from hundreds and hundreds of articles about Cleveland, a city that has battled perception issues for several decades," he said.

But Charlotte and Milwaukee face substantially new challenges in the age of the coronavirus. Case counts are rising in both North Carolina and Wisconsin; North Carolina recorded 1,200 new confirmed cases on a single day this week, its worst day during the outbreak so far.

Most agree that Republicans will conduct the actual business of the convention in Charlotte as planned. If Trump remains unhappy with Cooper's limited capacity requirements, he may decide instead to hold the equivalent of a MAGA rally on the day when he is expected to deliver the traditional address accepting his party's nomination.

It is not yet clear what would happen to the delegates who have arrived in Charlotte to conduct their party's business, those most dedicated party activists who want to cheer on the president. The RNC spokesperson declined to address how or whether delegates would be moved to a new city to hear Trump speak.

But so late in the game, few believe starting anew is a viable option.

"You really can't put two years of detailed planning in two months. And not just the planning, the execution," Gilbert said. "The time it takes to transform a regular sports arena into what typically is done in the staging and platform for what has been a typical political convention really can't be done in two months, the change to the physical space."