President Donald J. Trump is at it again with the Twitter account. U.S. drug stocks wobbled today after Trump tweeted that he is “working on a new system where there will be competition in the Drug Industry.” Today, the iShares Nasdaq Biotechnology ETF ( IBB ) and the iShares U.S. Pharmaceutical ETF ( IHE ) fell 1.3% and 1% respectively. But Evercore ISI analyst Umer Raffat asked this question -- “What does that mean?”