A riot is a a violent disturbance of the peace by a crowd. The key term of this is the word violent. And being violent under over someone who was democratically elected into office and who has not threatened their physical safety is absolutely immoral and unjust. If someone said something you don't like the answer isn't to act violently and childish. These are basic principles in life because if we all acted violently from something that someone has said the world would be a much worse places to live in. Not only this, but the riots are impact other peoples lives. If you are blocking highway, destroying buildings, bashing up Trump supports and whatever pointless things that achieves nothing they are doing, this is undoubtedly and unquestionably unjust and absolutely immoral.
Short answer: no. Since day one, there has been many untrue things passed around about Trump, like people saying he is a racist and homophobic. Despite the fact that Trump openly states he wants to protect those who are in the LGBTQ+ community and that he has friends that are Mexican and African American, the popular opinion was still that he hated gay people and people of certain races, and I believe that this misinformation has caused the Trump protests.
Obama has also helped fuel these illogical protests. In many of his speeches he has claimed that Trump is a racist and not informed on the issues of racism ("You may of heard Hilary's opponent in this election say that there's never been a worse time to be a black person. I guess he missed that whole lesson about slavery.") Obama ironically made the race relations in the United States worse.
Also, Hilary was clearly only in support of LGBTQ+ people so that she could win the popular vote. She is entirely a puppet, saying what people want to hear rather than having the guts to say what she actually thought. Rewind to 2004, and you can see Hilary in one of her speeches declaring that “Marriage is a sacred bond between a man and a woman.” (source: http://regated.com/2016/10/hillary-clinton-gay-marriage/). Now that gay marriage and the LGBT community is more relevant and favoured, how do you know that she isn't putting on a mask to win their votes? You could argue that opinions change, but I doubt it.
For some children in the United States, all they need to do is look out their window to see crowds of Anti-Trump rioters trash and burn their cities. Cases of assault, property damage, and more now circle the Anti-Trump riots in cities like Oakland, Portland, LA, and almost half the nation.
Those who riot and protest against the Trump Win on November 8th, 2016, consist of either peaceful, mild-tempered protesters, or violent criminals who would attack and vandalize their way until Donald Trump is no longer America's president elect, with the chances of such an event ever occuring highly slim.
This violence needs to end, and it has to end now. Some Democrats and Clinton supporters who have been peaceful or silent may go on with their way, free speech is a pillar in American society. But violence and crime is not justified in American society.
All in all, these 'riots' (NOTE RIOTS, NOT PEACEFUL PROTEST) can not be justified or supported by anything.