This is accurate, for the most part, though it's important to recognize that dissenting voices were silenced during the immediate pre-war and wartime years.
Contrary to what is commonly said, emperors in Japan were not seen as "living gods" (ikigami) until the late 19th century, starting with the Meiji emperor. Prior to that, the belief that they were descended from deities existed, but this was limited to those who even knew there was an emperor, which were a minority of the population. Nativists during the 17th and 18th centuries wrote about the imperial family as an unbroken line of descendants of the gods, the framework of ideas that became popular in the 20th century, but this wasn't widespread.
With the accession of the Meiji emperor in 1868, the rulers at the time started parading him around the islands to introduce him to the people. Popular reactions to the processions are pretty interesting - some people treated the visits as festivals, some thought he was Shotoku Taishi, the mythological founder of Buddhism in Japan, and some thought that he was a living god who, if you looked at him, would burn your eyes. After 1889, his movements and public appearances were more limited to the imperial palace in Tokyo and the parade grounds around there. This was also the time when imperial rituals were developed, like wedding ceremonies, anniversaries, rites for war dead, funerals, etc. All of these, and the rhetoric around them, had a hand in the creation of the emperor as a living deity descended from Amaterasu. By the Meiji emperor's funeral in 1912, this ideology was widely embraced by the younger generations of the public. The Taisho and Showa (Hirohito) emperors inherited this ideology.
A really well-written and comprehensive book on this is Splendid Monarchy by Takashi Fujitani. His central argument is roughly what I wrote above. He also looks at the creation of these traditions in detail and the technology (newspapers, telephone, transportation) that helped in the creation of nationalism in Japan. Another good book is Carol Gluck's Japan's Modern Myths.
TL/DR The Japanese emperor as a living deity was an active creation of the Meiji leadership at the end of the 19th century.
This particular conception of the emperor was manufactured at the onset of the Meiji period; the Meiji bureaucrats intended to emphasize the divinity of the emperor in order to legitimize the new regime's power (thus it's called the Meiji Restoration as it was presented as a coup to restore power to the emperor, though in reality the emperor was still in many ways a figurehead). The idea of the divine emperor was then disseminated through the national education system, beginning with the Imperial Rescript of 1890, which states that the Imperial Throne is "coeval with heaven and earth." You can see a gradual increase in rhetoric stressing the emperor's divine origins over the prewar period when you look at elementary school shushin, or ethics, textbooks, with educational materials produced during the war itself containing the highest amount. Going against this rhetoric was criminal; in 1930 the respected statesman and scholar Minobe Tatsukichi was forced to resign from all of his posts for suggesting that the emperor was but one organ of the Japanese state rather than the ultimate source of divine authority.
That being said, while the Japanese government did fiercely endorse the emperor's divinity, not all members of the general populace believed it. One couldn't state outright dissent, but by reading wartime diaries you can see that there was a decent amount of cynicism with the government and the imperial cult, especially towards the end of the war. The most fervent tended to be young men and children, as they had been the most affected by the increasingly nationalistic education system. The women's diaries I've read were less jingoistic, often characterizing the war as folly or a mistake (which contradicted the emperor's divinity in that he was supposed to be infallible). One diarist recalls an incident in which an older woman lost her son to the war and proceeded to write vehemently anti-war and anti-government pamphlets which she proceeded to anonymously send to everyone in the neighborhood.
There were also underground leftists who were anti-emperor throughout the period, but the government kept very close watch on anyone suspected of leftist activity and thus they had little influence or power during the war years.
Sources: Meiji Imperial Rescript on Education