President Barack Obama revived a familiar message Tuesday in his brief statement on the U.S. response to the Ebola virus: Calm down, we've got this. 

It's a common response from the president–one that has garnered its share of criticism and eye rolls as his administration has dealt with crises, real or otherwise, throughout his nearly six years in office. Yet it helps explain the series of policy decisions his administration has made in the weeks since the first confirmed case of Ebola reached the U.S. 

Amid elevated policy differences with governors and the heated political atmosphere that clouds just about everything seven days before an election, Obama has held firm throughout the debate over how to respond to spread of the virus. Calls for a travel ban were rejected out of concern it would prevent aid workers from reaching the region while at the same time having a crushing impact on the already severely stressed economies in the area. Calls for mandatory federal quarantine for health workers returning from the region have been dismissed out of fear that it would make the workers voluntarily traveling to fight the virus pariahs and unwilling to make the trip. It's a series of policy decisions that are equal parts dispassionate and, much as the characterization can frustrate the White House at times, professorial.

Obama's remarks on Tuesday tracked closely with what Tom Frieden, the director of the Centers for Disease Control and Protection, said over and over again on a conference call with reporters a day prior.

Policy decisions will be based on the science, Obama said.

They will be based on the facts on the ground, he added. 

They will be implemented on an individualized basis.

And if it just so happens to make certain governors (see: Christie, Chris) look political and prone to overreaction, well, that's an added benefit. 

"America is defined by possibility, and when we see a problem and we see a challenge, then we fix it," Obama said. "We don’t just react based on our fears."

The arrival of the virus on U.S. soil has thrown an added level of electorate anxiety into a combustible political dynamic that, by just about every poll out there, has trended away from Democrats. It hasn't just been Republicans criticizing the White House response to Ebola—Democrats made clear there were serious problems, as well. They pushed for a central coordinator of the U.S. response (and got one.) Many, especially those in tight re-election races, joined Republicans in calling for the implementation of ban on travelers from the region entering the U.S. (didn't happen.) The latest issue has been whether to impose mandatory quarantines, an issue exacerbated by a New York doctor who, upon return from West Africa, traveled around the city using public transportation, visited a restaurant and went bowling, spurring an ongoing campaign by health authorities to determine whom he may have had contact with.

Senator Mary Landrieu, a Louisiana Democrat fighting for her political life, came out Monday in support of a mandatory quarantine. New York Governor Andrew Cuomo joined Christie in implementing a mandatory 21-day quarantine for health care workers returning from the region. Their administrations received pushback from the White House for going too far. Yet Christie has remained firm, at one point saying the decision would eventually become federal policy. For governors, the issue is about protecting their citizens, even if the result is an abundance of caution, Christie said. He cited governors in both parties taking similar measures. The bottom line was this, Christie said this morning on the Today Show:

"The American public believes this is common sense and we’re not moving an inch. Our policy hasn’t changed and our policy will not change."

The different paths taken by governors have added an element of confusion and underscored the patchwork nature of how the U.S. is responding at home—something Frieden acknowledged Monday on his call with reporters. "It's within their authority in the system of government we have," he said, though he added that the CDC has been in close contact with states on how to respond. The U.S. military is also imposing different requirements for troops returning from deployment to the region. 

Yet Obama has given no indication that he will move any further toward Christie on the issue. Instead he moved Tuesday to tamp down fear of the virus, noting that "it's important for the American people to remind themselves that only two people sof ar have contracted Ebola on American soil." Both are now disease-free, he said.

The revised CDC guidelines released on Monday recommended a 21-day home quarantine for high-risk travelers returning from the region. Returning health care workers would be monitored closely and could voluntarily quarantine themselves, but there would be no mandatory isolation. With health workers making up only about 4 to 5 percent of the travelers coming back to the U.S., administration officials stress that it is with within the capability of states to monitor each returnee in an active and individualized manner. That's the policy Obama's advisers on the issue have recommended and that's what he's sticking with, he made clear on Tuesday.

"We don’t want to do things that aren’t based on science and best practices, because if we do, then we’re just putting another barrier on somebody who’s already doing really important work on our behalf, and that’s not something that I think any of us should want to see happen," Obama said. 

White House officials have been cagey about the interactions between the New Jersey governor's office and the president. White House Press Secretary Josh Earnest would say during Tuesday's press briefing only that "there are administration officials from a wide variety of agencies that have been in very close touch with New Jersey officials" over their Ebola response. 

Obama was asked, as he walked to Marine One for a trip to campaign and raise money in Wisconsin, whether he had talked to Christie directly. He didn't respond, though he didn't really have to. He'd made his point already.