Because they listen to the Gospel according to Sean Hannity.
Trump and his toady minions are masters of misdirection.
Mostly because it has to be his fault. Everything is his fault or Hillary's because it cannot be Trump. Donald is hated in many parts of the world and his supporters don't know why. It has to be "fake news." Nobody understands why London would fly a baby "Trumpelin." People here know that Trump cried foul on Obama's birth from day one and Trump is still blaming Obama for many things. If not Obama then we switch to Hillary and her "many crimes." Trump supporters just don't understand why she hasn't been "locked up." After all, Donnie promised it. Then we have the Trump "border wall" with Mexico. Contrary to what you hear no one is building that one just yet. They are repairing sections that were set to be repaired. As for the Trump wall, why don't they just use Hillary's e-mails? Nobody has been able to get over those yet.
People don't seem to understand that when they pass off what I'm saying and do so very lightly, they are only justifying Trump and his moronic and outrageous actions.
Mostly people on the Right trying to deflect attention from their Dear Leader. The eight years Obama was in office the Right Racist jackals were doing everything in their power to spread lies and disinformation on the first non white president. Add to that a majority Republican congress sworn to do nothing that would benefit the middle or lower class, it kind of makes for a lame duck president. With any luck we can do the same to Trump this November if the Russian don't come up with a means of totally sabotaging the elections.
Be aware of a system called Cross Check that is a program out of Kansas. It is said the checking system is to guarantee that Smith and Jones did not cheat and vote in other states. That idea is preposterous but it was used on Democratic votes only. (I wonder why?) I'm expecting they will try to use something like this again.