You tend to think Iran's mad mullahs understand U.S. politics well enough to know that Trump is a very different animal from his predecessor. But do they really understand the lay of the land? Or do they understand it through the prism of radical Islam tinted by the filter of the U.S. news media? A provocative move like a ballistic missile test seems awfully foolhardy if you believe the caricature of Trump as an erratic lunatic who just might punch in the nuclear codes and laugh while doing it.
Then again, the mullahs knew they could poke at Obama all they wanted without paying a price. Obama was so invested in his nuclear deal that it was impossible for him to ever publicly acknowledge Iran was acting up, lest he undercut the credibility of his own judgment in negotiating the deal and in trusting the Iranians to live up to their end of it.