During the construction of the Hotel Utah in 1910, a bomb demolished the iron frame that had been erected:
A few minutes past 3 a.m., a terrific explosion, fueled by dynamite and nitroglycerin, erupted from the northeast corner of the construction site. The concussion knocked one of the watchmen to the ground, twisted part of the hotel’s iron framework beyond repair, and shattered windows in the office buildings across South Temple. In the words of one witness, there was “not enough glass left to make a pair of spectacles.” Downtown residents covered in dust and shards of glass ran into the street, some convinced that the comet had actually struck Salt Lake City.
Although office buildings across South Temple were damaged, the Temple across Main Street luckily remained undamaged except for displacement of the Angel Moroni’s horn.
It turns out that the bomb — together with another that detonated the previous December — was an act of terrorism perpetrated right in Salt Lake City by supporters of a national workers’ union:
Investigation began before daylight, with suspicion instantly falling on the ironworkers’ union, which had objected to the open-shop policy of the hotel’s contractor. The union also was suspected the previous December when a similar bomb exploded in the hotel’s foundation, but no solid evidence was found to link either crime to any culprit. . . .
More than two years later, the Hotel Utah bombings were solved when three men – including McNamara, the union man who had offered a $500 reward – confessed to having set both bombs, along with dozens more around the country, one of which had killed 21 men working at the Los Angeles Times.
In these days when headlines of terrorist bombs dominate the daily news, who would have thought that Salt Lake City was dealing with labor terrorists using similar techniques nearly 100 years ago?