The change of plans was announced Monday as Chicago prepares to be placed in the global spotlight.
The G8 was originally scheduled to take place on May 19-20 at McCormick Place. The NATO summit was set to take place on May 20-21, also at McCormick Place.
Now the G8 will be held on May 18-19 at Camp David. Chicago will still host the NATO Summit on May 20-21.
During a press conference Tuesday, President Barack Obama said he is confident Chicago can host the NATO summit.
"I always have confidence in Chicago being able to handle security issues," he said.
It wasn't a security issue that prompted the decision to move the G8, the president said. It was a desire for a more intimate setting for the G8 leaders that Camp David would provide.
"G8 tends to be more informal," Obama said. "The thinking was that people would enjoy a more casual backdrop."
If it was solely a matter of a more intimate venue, could not that decision have been made months ago?
Whatever the reasoning, there is both concern and relief with the G8 saying goodbye before it even got to Chicago.
"The elimination of those two days is a sigh of relief," said Connie Murphy, vice president of marketing, Mercy Hospital.
Murphy is the chairwoman of the South Loop Planning Board, which has among its members many of the businesses that surround McCormick Place, where the G8 was set to take place. They were supposed to hear from the NATO host committee Tuesday, but got no detail because a lot is in flux.
Hoteliers, such as the Chicago South Loop Hotel, are a bit concerned.
"We did have some group bookings at the hotel, so it is going to be concerning," said Sheila Ward, Chicago South Loop Hotel.
The big picture argument is that Chicago still has NATO, which will bring six times the number of people that G8 would have. But it's the G8 leaders who provide the star power and bring many of the international journalists who are expected to write glowingly of the host city.
The South Loop businesses are keen on promoting Chicago.
"But we still have questions on what's going to happen, what's the process," said Bonnie Sanchez Carlson, South Loop Planning Board president.
Mercy Hospital is just across the expressway from McCormick Place. The hospital is hoping it's business as usual come NATO. That's dependent on a security plan designed by Secret Service and enforced by Chicago police.
"We have a lot of questions. How are our employees going to access the hospital?" said Murphy.
"We know how to deal with crowds and I'm sure that your new mayor will be quite attentive to details," said Obama.
Aldermen want answers from mayor
A City Hall spokeswoman says Mayor Emanuel, the former White House chief of staff, had no more than two hours advance notice that world leaders would not be coming to Chicago. The presumably disappointed mayor had no choice but to accept the decision by his old boss, Barack Obama.
Emanuel issued only a written statement Monday, saying, "we wish President Obama and the other leaders well at the G8 at Camp David and look forward to hosting the NATO summit in Chicago" that begins May 20th.
But some aldermen ABC7 talked to wanted more direction from the Emanuel administration.
"It would be good for them to come out and say here are the specific changes and here's what we have to weigh in on," said Ald. Scott Waguespack, 32nd Ward. "I haven't seen him, I haven't heard anything."
An Emanuel spokeswoman tells ABC 7 the mayor left Tuesday for an unannounced trip to New York City to "recruit new businesses" for Chicago.
Alderman Walter Burnett said the G8 switch reveals how little control Emanuel actually had over the event.
"Washington D.C. is in charge of international things and things that deal with our nation," said Burnett. "Not the mayor, not at all. And the mayor, I think was just being a host and trying to help out."
Alderman Bob Fioretti, who opposed G8, said the NATO meeting will present the same problems if only during a shorter time frame.
"The precautions that were being set up before are the same precautions that are being set up now," said Fioretti.
His spokeswoman says Mayor Emanuel will return to Chicago Tuesday night. There is no word as yet on his next public appearance or availability to the media.
Concern, relief among business owners after G8 move
Summit organizers who have been working around the clock are shocked and disappointed they are losing the historic opportunity to host both events. Hotels and restaurants are hoping they don't lose any business.
On the other hand, there is relief among businesses that were preparing for protests.
The South Loop restaurant Yolk is more than happy for Chicago to have some egg on its face. Gearing up for violent protesters, its owner was preparing to board up his place.
"I'm actually relieved a little bit," said Taki Kastanis, owner. "I think hopefully security issues they were concerned about would be a little less now."
Don Welsh, the CEO of the Chicago Convention and Tourism Bureau, says Chicago is prepared for the worst. Welsh is disappointed the city is losing the opportunity to show the world it could have handled both summits.
"It was a little difficult to swallow, but you respect the president's decision," Welsh said.
With the announcement so new, Welsh says so far no hotel contracts have been canceled. While fewer visitors are expected, Welsh still expects over 2,000 international journalists to visit Chicago which he says is the key to showing off the city to the world. And with six of the eight world leaders attending NATO, Welsh says their delegations are already spending money in Chicago.
"These delegations have made numerous trips to Chicago to get ready for this," said Welsh. "They've been in hotels and restaurants and they've been to our attractions and our museums. They're generating a lot of economic impact now."
But University of Chicago economist Allen Sanderson says the economic impact of both summits was overblown.
"Any economic impact statement you could get on how much is this worth to the city just in raw dollars is a gross overestimate," said Sanderson. "Take whatever number they give you, divide by 10 and that's probably much closer to the truth."
Sanderson says the impact is even less without G8.
"It's the better of the two summits, in part because it has some economic coat tails in a way that NATO really doesn't," he said.
Sanderson says NATO is about security while the G8 brings in world leaders with entourages that are in a business frame of mind.
Without G8, the convention and tourism bureau says it is too early to determine what kind of fall out there is in terms of numbers.
Protesters: We're still coming to Chicago for NATO
Protesters say the change is a huge victory but they say they will still be out in force.
"Guess what? The protests are going to happen anyway because if (protesters) are upset about G8, they have just as much reason to be upset about NATO," said Andy Thayer, a leader of the Chicago Coalition Against War and Racism and the Gay Liberation Network and one of the principle planners of the Chicago protests.
The White House said the economic summit was moved "to facilitate a free-flowing discussion with our close G8 partners," on economic, political and security issues.
Some protesters took that as a sign they'd run the summit out of town.
"It's a major victory for those of us who are planning these protests," said Joe Iosbaker, head of the United National Antiwar Committee in Chicago. "The administration is taking G8 someplace where they won't have to face the people who suffer under their policies."
Chicago police spokeswoman Melissa Stratton said Monday's news won't change how the department prepares for the NATO summit. Members of the city's host committee said they still expect about 7,500 people to attend the meetings.
Camp David, the presidential retreat outside Washington, where the G8 meetings will be held, is far more secure than downtown Chicago and it would be difficult, if not impossible, for protesters to get close to the meetings.
ABC 7's political analyst Laura Washington says terrorist threats from Iran and economic threats from Europe likely prompted the move from Chicago.
"I suspect there might have been some threats that we aren't aware that gave them pause," said Washington. "That made the president realize he could to this much more efficiently at Camp David."
With the G8 leaving, the two-day NATO summit, which convenes a large group of world leaders, will remain at McCormick Place on May 20-21. It is the first time an American city other than Washington has hosted it and Chicago will still be in the global spotlight.
"The NATO summit is such an important event...28 member states," said the Chicago Council for Global Affairs' Rachel Bronson. "All the countries participating in Afghanistan will be coming. Lots of really important issues on the agenda, and we're focusing on that."
Mayor Rahm Emanuel was excited to be hosting both summits in the same place at the same time. Through a statement, he said he is still excited to be hosting the NATO summit in Chicago, but he has not made a public comment yet.
The Associated Press contributed to this report.