Why Is There a Powerful American Warship Docked in Manila?

There is a formidable American warship docked in Manila Bay on September 27. The USS Tripoli is one of the U.S. navy's newest warships. It was launched in 2017 and delivered to the U.S. Navy in 2020. Currently, it is crewed by over 100 officers and 1700 marines.
Despite its looks, the USS Tripoli is not an aircraft carrier (even if it does carry warplanes) but is considered in military parlance, an amphibious assault ship.
The warship is in Manila for a port visit.
The USS Tripoli with 20 F-35B Lightning II Stealth Fighters

Port calls are goodwill visits of military ships to ports of foreign nations. Such visits are common among friendly nations, especially during joint maritime exercises between nations. Port calls are also used by the crew to refuel or resupply their ships with food, water, and other provisions.
The USS Tripoli was recently in the Philippine Sea where it conducted drills on search and rescue operations. It was also involved in freedom of navigation operations or FONOPs in the Indo-Pacific region.
Below are some of the posts of the USS Tripoli tagged as #FreeAndOpenIndoPacific.