To be as clear as possible: even with the absurdity of the tweet, it is very bad that Trump just started a war.
To be clear as possible, this makes the World a safer place...Iran is a terrorist state that has been promising to destroy Israel and the U.S. for 40 years...
To clear….you don’t know that. You are relying on a state that lies (Israel) and a man who lies. Israel has been promising to destroy countries as well
Just another "emergency" that Trump will use to consolidate power and arrest people who protest against this. See: Alien and Sedition Acts 1798, Espionage Act 1917, Sedition Act 1917, Schenck v. United States 1919, Japanese internment 1940s, McCarthyism 1950s, just to name a few.
Technically, the term "war" implies that there are two combatants capable of striking blows against one another. It remains to be seen what, if any, damage Iran can inflict on the USA.
As things stand, this is not a war but instead a super power imposing it's military might and geopolitical will against an technogically inferior, regional pariah state.
A state of war would only be established if the USA, or even less likely, Iran, were to send ground troops into the other nation's country to claim and occupy territory. Trump, or any US president, is unlikely to pursue a conventional ground campaign because of the risk of asymmetrical guerilla and insurgent warfare.