Yes. An ideology that advocates racial supremacy, ultra-nationalism, conservatism and far-right authoritarianism should be treated with extreme scepticism and if push comes to shove, violence. I do not believe violence should be the first path. First, they must be debated, but if they do not listen and continue to spread their hateful agenda they should be bullied and treated with contempt. There is no place in a civilised, nor democratic, society, for an anti-democratic and authoritarian ideology
Violence should always be the measure of absolute last resort, but when faced with a totalitarian fascist regime it may be necessary. Contemporary liberals are very close to that line. Over the last 12-14 years we've seen the decent Democratic party of strong, moral Presidents like Roosevelt and Kennedy hijacked by an oppressive faction of political correctness fascists.
The current liberal agenda in America appears to be the total suppression of disagreement or dissent and the complete oppression and subjugation of the people under an all-powerful central government. And yes, it might require violence to fight back against it.
Obama's rather extreme abuses of power have now exceeded those of George III in the late 18th century, which gave birth to ideas such as:
"The tree of liberty must be refreshed from time to time with the blood of patriots and tyrants"-Thomas Jefferson
"Give me liberty or give me death"-Patrick Henry
"But when a long train of abuses and usurpations, pursuing invariably the same Object evinces a design to reduce them under absolute Despotism, it is their right, it is their duty, to throw off such Government, and to provide new Guards for their future security."-United States Declaration of Independence
So yes, violence is justified when faced with a totalitarian fascist dictator such as Obama or HRC.
One more, just to show that the concept of standing up to a dictator is not just from the American Revolution:
"It's better to die on your feet than live on your knees"-Emiliano Zapata
Violence committed against others that merely hold ideas that you disagree with is wrong, on all levels. The question deals with "Fascism." Fascism is a form of government that suppresses free speech and many other individual freedoms. Fascism is dictatorial in nature and may require a coup or overthrow to suppress the fascist government's perpetration of human rights. So, yes, actual fascism may lead to a violent overthrow by citizens whose rights have been suppressed.
However, many uneducated--young people especially--equate "conservative", "republican", or "nationalist" automatically with fascism. This is completely illogical. Conservative policies attempt to stick close to the constitution and preserve human rights, more so than "progressive" ideologies which attempt to morph and mold the constitution to make more and more rules and regulations, that eventually grow the government --which actually ends up in a loss of civil liberties.