Mark your calendar for late May.

That’s when President Trump starts a summer of overseas trips that have nothing to do with opening golf courses.

It should be a fascinating time as the Loud One takes his reality presidency abroad to alter or confirm widespread impressions of the new American leader. Will he perform as he does at domestic rallies? Or will he impress as he did in a January speech to Congress and during the campaign when the candidate traveled to meet with Mexico’s president and looked comfortable and poised like a real president?

Successful foreign trips by presidents have been known to impress Americans back home, where Trump’s approval rating floats underwater.

One thing for sure: The 45th president has a wide array of inherited foreign policy problems. But he will not be apologizing for America when he visits Italy, Belgium, Germany and Great Britain.

Trump’s summer itinerary so far begins in late May with a trip to Brussels for a NATO leaders meeting. The president has already sent Vice President Pence and Defense Secy. Mattis there to reiterate strong support for the alliance, despite his campaign description of “obsolete.” Trump has said numerous times since how important is the alliance that Russian leader Vladimir Putin would love to help fray.

But he’s also said each time that it’s past time member countries live up to their long-neglected promise to invest 2% of GDP in defense spending because he won’t be picking up the slack anymore. In February, Pence played the bad cop and provided a time-line of December for significant progress to be made in that area by NATO’s 27 other members.

As is his operating style, Trump has already begun building personal relationships through long telephone conversations with many leaders, including NATO Secretary General Jens Stoltenberg, who will visit the White House April 12.

At home and abroad, Trump will be closely watched by foreign leaders, their teams and, of course, their media.

Also in late May, Italian Prime Minister Paolo Gentiloni will host a meeting of the G-7 industrial nations in Taormina, Italy. Trump already accepted his invitation.

During her White House visit last week, the president also accepted an invitation from German Chancellor Angela Merkel to attend the annual G-20 economic summit in early July in Hamburg.

At the invitation of Queen Elizabeth II, Trump has also agreed to make a state visit to Great Britain, likely some time this summer. That will come as Britain enters formal discussions to leave the European Union, a step Trump supported as a candidate before the Brexit referendum last year. After Prime Minister Theresa May’s Oval Office visit this winter, bilateral trade talks will almost certainly be on the agenda.

Trump is keen for them. His predecessor, who opposed Brexit, seemed to threaten the Brits with going to the back of the negotiating line if they voted to leave Europe.

And then, of course, there’s Vlad. The Russian and American leader have agreed to meet, likely sometime later this year. Slovenia is a possible site. That’s where Putin first met President George W. Bush in his first year. More importantly, it’s the homeland of Melania Trump.