Not all Croatians are fascist. However, those who are have major influence in Croatia
"If you got a slave master or Klan in your blood, blacks can sense that. Just like Jews can sense Nazi blood and the Serbs can sense Croatian blood." -- Bob Dylan
This comment was from a September 2012 interview of Bob Dylan for the French edition of Rolling Stone magazine. He was referring to racism still being a social problem. Politically-speaking, it was ignorant. But Dylan would not/could not refer to ALL Croatians as fascists.
The Council of Croats in France (CRICCF) thinks so, suing Dylan for encouraging "hatred" and "racism" against Croatians, the implication being all Croatians.
Serb-Croat relations were brutal in the 20th century, specifically in WWII, and the 1990s Yugoslavian Civil War. Serbs were the primary victims during WWII. "More than half a million Serbs were killed, a quarter million expelled, 200,000 forced to convert to Catholicism of the Croatian fascists."  During the Civil War, Croatians and other ethnic groups were victims; but that also included Serbs: In Krajina, with a Serbian population, a United Nations report stated that "[n]ew evidence for atrocities continues to emerge...six corpses a day...some fresh, others decayed...many were shot in the back of the head or had their throats cut. The crimes were committed by the Croatian army, Croatian police and Croatian civilians." 
But Serbs were portrayed in media as THE villain, where it was reported that they did the killing, raping, etc., while other ethnic groups were portrayed as victims only.
The stakes were high in Yugoslavia during the civil war. The outcome either meant that a country would stay together, or be dissolved and taken over. The latter was the unfortunate fate for Yugoslavia.
History of the Ustase
During WWII, the Ustase (or Ustasha) was a Croatian fascist "revolutionary" movement which operated what was called the "Independent State of Croatia (NDH)." The latter was a symbol of the occupation by Nazi Germany, which appointed the Ustase to rule that part of Yugoslavia.  Their leader was Ante Pavelic, "the Real Butcher of the Balkans."  For the Ustase, Catholicism and Islam were the only true religions in the NDH.  Their kind of nationalism, politics and ideology qualified them to be labeled a terrorist organization.
Notably, the Ustase killed a vast number of people in the Jasenovas prison camp: this included Serbs, Jews, Roma (Gypsies) and anti-fascist fighters.  It went on its own ethnic cleansing campaign.The meaning of the name ustase (or ustasha) was derived from the term Pucki-ustasa, which was an imperial rank in the Croatian Home Guard from 1868 to 1918. But it came to symbolize fascism, the meaning of a military-corporate state. Even without this meaning, it still symbolized feudalism and monarchy, given the earlier history. 
Civil War (and Foreign Interference)
In March 1991, Croatian fascists and separatists carried out attacks and violent demonstrations. This ignited the civil war. During the civil war, "right-wing fascist organizations-not seen in 45 years since the defeat of the Nazi occupation-were suddenly revived and began receiving covert support. These organizations had been maintained in exile in the U.S., Canada, Germany and Austria. They became the main conduit for funds and arms." 
There was foreign interference in the form of the Operations Appropriations Law 101-513,passed by the United States Congress, giving the U.S. an "excuse" to sabotage Yugoslavia's economy by cutting off all aid, trade, credits and loans. It also gave the U.S. position of being like some neo-colonial power, ordering that elections be held and devising the procedures for them. Europe joined in with an ultimatum: proceed with "free" elections or face an economic embargo. 
With the dissolving of Yugoslavia, Croatia became its own nation in 1991. A modern day Ustase came to power. "It used fascist symbols and slogans from the era of Nazi occupation. Its program guaranteed a return to capitalist property relations with no basic rights for other nationalities, but especially targeted the Serb minority."  The Serbs sensed a redo of WWII atrocities and began to take up arms.
The new Croatia tried to distance itself from the legacy of the former Independent State of Croatia. Free expression became a reality. And with that, the emergence of ultra-right parties/groups. But benefit of the doubt was significantly given to the Ustase for their desire to make Croatia independent (with Nazi occupation?). As a result, hate speech from the right was allowed.
Croatia's first president, Franjo Tudjman, a fighter against the Ustase in WWII, wanted ALL Croatians to unite, regardless of political views. With that, neo-Ustase Croats spread their political and ideological views of fascism. No new laws were passed in the 1990s targeting the banning of such views, given Yugoslavia's brutal past.
Tudjman was no pro-democracy icon. "Tudjman almost certainly did not care that he was a monster because, unlike [Slobodan] Milosevic, he was our monster," wrote author Misha Glenny.
Recently, sports, namely football (soccer), is an outlet for fascist symbolism: a fascist salute to the Croatian crowd by team captain Josip Simunic, and shouting "Za dom!" with the crowd replying Spremni!". This is like shouting "Sieg!" Heil!"   And in a recent referendum in Croatia, 65% of the population supported a constitutional ban on gay marriage. 
The CRICCF's attempt to successfully sue Bob Dylan should prove futile. Dylan wasn't totally out of line with his comments. In today's Croatia, fascism appears alive and well.
David Starr writes on social and political issues, both national and international.
 Rosenthal, A.M. "Fascists Of Croatia Back From The Grave." The Sun Sentinel, April 1997: pg. 1
 Leicht, Justus & Schwarz, Peter. "Croatian President Franjo Tudman Dies." World Socialist Web Site: pg. 1
 Britainnica Encyclopedia Online. "Independent State of Croatia." http://www.britainnica.com
 Markowitz, Norman. "Croatian Fascists and the Attack on Bob Dylan." People's World, December 2013: pg. 3
 Ibid. Britainnica Encyclopedia Online.
 Flounders, Sara. "Bosnian Tragedy." October 1995: pg. 4
 ibid. pgs. 2, 3, 4
 ibid. pgs. 4, 5
 Atkinson, Rodney. "Croatian Fascism on Display Again - Friends of Cameron and German Europe." Free Nations, November 2013: pg. 1 http://www.freenations.freeuk.com
 B92, Tanjung. "More pro-Fascist Incidents in Croatian Stadiums." b92, November 2013: pg. 1
 Kampmark, Binoy. "Creeping Towards Fascism?" Counterpunch, December 2013: pg. 5