Were groups that advocated the use of violence in the 1960s justified in doing so? Why or why not?

Very few groups in the 1960s advocated violence, except the US government, in the form of military adventure, where they went far beyond advocating. A total of about 1,353,000 deaths occurred on all sides in the Vietnam war. Then there was/is the Klu Klux Klan. We need to be watchful even now. The Weathermen were a small organization and they claimed not to intend violence, but use it if “necessary.” The Black Panthers called themselves a party of “self defense.” Whether or how often individuals in the latter two groups deviated from their charters (if any) is hard to determine.

Anyway people can justify their actions of violence it doesn't mean it was justification for everybody.

nothing certain is known about what happened, but it seems that the country declined gradually, perhaps due to bad government, or, more likely, due to a series of bad harvests, which resulted in widespread and recurrent famine.

the industrial development of cities in the ruhr area in the nineteenth century is described. the research was based on english and german language sources. several factors that shaped growth and paths of the cities were categorized and analyzed. they are locations, resources, traditions, entrepreneurs, and technological developments. locations and resources were the most important among them; other factors may be regarded as consequences from locations and resources. among the cities, bochum, essen, gelsenkirchen, and dortmund had the richest resources and most favorable locations in the transportation network and grew to be the largest cities in the ruhr area near the end of the nineteenth century. riverside location was also a favorable factor for the development, as shown in the development of duisburg on the confluence of rhine and ruhr. resource distribution can explain the rise of textile industry, metallurgical industry, and coal and iron industries, and the northward progression of the mining industry. tradition was an important factor for cities such as krefeld, barmen, elberfeld, solingen, and remscheid, which experienced development based on their traditions through the nineteenth century. various entrepreneurs exerted influences within and beyond the local level over the ruhr area. technological development stimulated the northward progression of the mining industry and the deep connection between the coal and the iron industries.