When Democrats run things, they run them into the ground. This is partly because Democrats are lawless and unethical, and they don't believe that any laws or rules of civil society apply to them. As we've all seen, powerful Democrats can commit almost any imaginable crime -- including rape, sexual assault, money laundering and campaign finance fraud -- while facing no consequences whatsoever for their actions.
Any time Democrats have power over any institution in society, they destroy the credibility of that institution: The EPA, IRS, FBI, etc. Let's also not forget that Democrats ran the KKK, Democrats were the party of segregation of blacks, Democrats opposed the 1964 Civil Rights Act, and Democrats opposed Abraham Lincoln, the Republican President who freed the slaves.