This clip explains why for me.
The American government's foreign policy under Bush and Obama has been a disaster for the world, especially for the muslims. Radical Islam is worse than ever. Takfiri ideology used to be a stage 1 cancer requiring a surgical cut. Today it's stage 4 requiring a world wide chemo session. Here is a short list of American blunders in the last 15 years alone;
An alliance with Pakistan, who protects the Taliban and hid Bin Laden
An alliance with Saudi Arabia, who is spreading their Salafist ultra-conservative Islam throughout the Islamic World and building hate preaching mosques in Europe.
Invasion of Iraq over false pretenses. Iraq is now an absolute mess
Supporting Syrian rebels, some of them are jihadi factions
Assisting with the overthrow of Qaddafi, Libya is now destroyed
An on going proxy war against Iran, using bullshit 'nuclear weapons research' to wage economic warfare. Nothing conclusive was ever handed to the IAEA to prove Iran actually had a military aspect to their program. It was all about fighting over hegemony. And the USA still lost anyway. Iran used to be isolated and scared and now they control half the middle east.
The establishment's foreign policy has been a failure on all accounts and has destroyed much of the Middle East in the process. Trump is going to make the right decisions in the Middle East because he's not an arrogant lunatic like the MSM portrays him to be. He's a businessman and negotiator and will make deals and compromises with all Parties, using his professional experience to get the best deals America can possibly hope to get in the process. This is the right way to go about foreign policy. If you put someone like Shillary in she'll have the Pentagon on speed dial and geopolitical rivals like Russia and Iran will just retaliate in their own way playing by their own rules. And things will continue to get worse. And Sanders, although his intentions might be pure, I don't think has the aptitudes Trump has to do things better.