He is a colorful character, trying to fix the mess in his country. The US empire goes to specific countries to issue their moral high ground to others. Obviously the Philippines president has had enough of being lectured to be a puppet leader for the west, and snapped by calling Obama names.
If only, there were more leaders like Rodrigo Duterte in the east, people who have the balls, to stand up to globalists. The Philippines has loads of issues, poverty, crime and drugs, drugs is more severe in that part of the world. Now, one can debate the actual tactics that are being used to deal with drug users, however one needs to keep in mind that each country, culture, and structure differs from one another.
One will never hear the abuse being committed in MENA region from the western empire, having Saudi Arabia in the UN human rights commission is a joke, as the western civilization depends on petroleum and will turn a blind eye to their activities. For other countries they always like to control them by keeping a puppet, or threaten them with military action, and aid.
The game has changed, with more superpowers rising in the east, the same tactics the west had used will no longer work. Rodrigo Duterte is proving himself to be a shrewd diplomat, standing up for what he believes in and maneuvering his policy to get necessary support. Other cowards need to take notice and learn to lead.