Trump's Canada. What's really going on?

Trump has publicly said we will make Canada a US state, annex or buy Greenland, and reclaim the Panama Canal. This has caused the American leftists, European Union leaders, and some Central American leaders to get loud on TV and social media. It has also confused a few conservatives that got blindsided by the news. So why did he do it? And which parts are serious? I'll break it down as fast as I can.