Remember when President Barack Obama first came into office in 2009?

Roger Dow does, and it didn't start out as a very pleasant memory. But Dow, chief executive of the U.S. Travel Association, a major trade group, hopes that what the travel industry learned from that time will help erase another unpleasant memory:

Remember when President Trump first came into office in 2017?

Dow told the story of these two presidents and their early unhappy relationship with the travel industry to hundreds of people in Philadelphia's hospitality industry gathered Wednesday at the Convention Center for the Philadelphia Convention and Visitors Bureau's annual report, including results from the Democratic National Convention.

Obama, Dow said, had just taken office as the economy was in the midst of the recession and the travel industry was still suffering from the effects of the Sept. 11, 2001, terrorist attacks.

The Wall Street bailout was underway, but there were still reports of lavish travel spending by executives. Obama sharply criticized highly publicized Wall Street junkets to pricey conventions on the West Coast.

The travel industry, already struggling, howled in protest and snagged a White House meeting with Obama adviser Valerie Jarrett, when, unexpectedly, Obama showed up, Dow said.

"He said, 'I know you're not happy with me,' " Dow recalled, noting how his group explained the economic impact of tourism along with the jobs it supported at a time when the unemployment rate was soaring. "We could watch this new president saying, 'Wow, now I get it.' "

Fast forward to 2017, when Trump, barely inaugurated, imposed a travel ban on visitors from seven majority-Muslim countries and suspended the State Department's visa-interview waiver program, which allowed regular foreign visitors, including business visitors, to skip face-to-face interviews with consulate officers when their visas expired.

Now, Dow said, it's Trump who needs to be schooled. "People from around the world, their hair was on fire. They said, 'People in the U.S. don't want us.' "

The impact was immediate.

Philadelphia lost a convention that would have had a $7 million economic impact when the group decided to take a pass on the U.S. and book its convention in Canada or Mexico, said Alethia Calbeck, director of communications at the Philadelphia Convention & Visitors Bureau, declining to identify the group.

"We were up for a piece of business, and the organization decided to not have its meeting in the United States," Calbeck in an interview in February. "They have a largely international audience and wanted to be sure everyone would be able to attend their meeting."

"This too shall pass," Dow told the group on Wednesday. "It's going to be all right, but we have work to do" lobbying the Trump administration.

After all, his group has estimated, the U.S. travel industry produces $2.3 billion in direct and indirect economic impact, supports 15.3 million jobs, either directly or in related industries, and generates $157.8 billion in federal, state and local taxes.

That's why, Dow said, the travel industry has to get behind a single unifying message: "America is closed to terrorism, but wide open to everyone else."