Why did Trump and Macron meet as two political "outsiders"?

On the evening of May 24th, local time, Trump arrived in Brussels, Belgium.

Because of his arrival, Brussels entered the highest level of the strongest alert state. Among the more than 4,000 new police officers, some are temporarily seconded from the Netherlands. In fact, due to the lack of police force in Belgium, the security of Trump during his stay in Belgium was the responsibility of the police in Belgium, Luxembourg and the Netherlands.

Specific circumstances:

Trump, who once criticized the danger in Belgium, did not choose to stay in any hotel, but chose to rest at the US Embassy in Brussels. This makes the American security department investigate the residents living in nearby streets one by one, which seriously interferes with the lives of local residents.

In addition to staying at the US Embassy, Trump also chose to host Macron at the embassy at noon on May 25th local time. Earlier, White House officials revealed at Trump's pre-trip briefing that since Trump and Macron are both newly elected leaders of big countries, they will exchange views and opinions during a "long lunch".

The White House official said that Trump thought Macron, 39, was impressive and won a dazzling election, while Trump and Macron were "outsiders beyond traditional political barriers".

Trump once expressed his hope on Twitter that Le Pen, a French far-right candidate, would win the election. This time, the White House official clarified this, saying that the tweet was "misread" and infinitely magnified.