Is there any particular significance behind "I Am Legend" being set in the late 70s?

Question

Richard Matheson's brilliant 1954 novel I Am Legend takes place between January 1976 and January 1979, with several flashbacks to 1975, when the vampire plague began to spread.

Throughout the novel, there are several references to a "war" which, the way I read it, likely happened less than ten years before the events.

“Oh, it means they're . . . changing [the insects]. Suddenly. Jumping over dozens of small evolutionary steps, maybe developing along lines they might not have followed at all if it weren’t for . . .”
Silence.
“The bombings?” she said.
“Maybe,” he said.
“Well, they’re causing the dust storms. They’re probably causing a lot of things.”
She sighed wearily and shook her head.
“And they say we won the war,” she said.
“Nobody won it.”

_{I Am Legend, chapter 8}

Robert Neville is born in 1940, give or take a year (as he's described as being thirty-six in the first chapter, which takes place in 1976). Thus, the war he refers to when talking with Ruth is unlikely to be one of the latest major wars the year 1954 had faced (World War Two, Korean War).

“I don't know about you. As for me, while I was stationed in Panama during the war I was bitten by a vampire bat. [...]”

_{I Am Legend, chapter 17}

I understand the novel was written at the beginning of the Cold War, shortly after the first thermonuclear bombing test (known as Ivy Mike, 1952) and the Korean War (1950-1953). I guess that setting the story in the future was the most logical way to introduce a new "war" and its aftermath, while still appealing to 1954's concerns.

However, I wonder whether a politician/newspaper/rumour may have predicted a new war to end specifically in the mid-70s, or if these years were supposed to be some technologic turnaround (relevant to the novel's plot), or anything like that, which would justify the timeline.

Has Richard Matheson ever stated whether the late 70s were meant to have a historical significance (or any kind of significance)? Or why he specifically chose the 70s over, say, the 80s-90s?

I'm mainly looking for a statement from Richard Matheson himself, but as always, educated guesses are welcomed.

If it's of any help, here's a Paint-drawn timeline of the events described above:

Answer 1

This is a standard technique for science fiction: you set something a few decades into the future so that the culture isn't likely to be too unfamiliar to the reader/viewer, and yet there's enough time for there to be the changes and events you want to set up to set the scene for the story you're telling.

2001: A Space Odyssey came out in 1968, giving a 30-odd year margin for the technological advances seen in the film while still having familiar things like clothing, Soviet-American relations, and so on. Star Trek in 1966 had Khan Noonien Singh involved in the Eugenics Wars in the 1990s. Space:1999 was filmed in 1975-1977, and so on.

TVTropes has many examples under the topic "20 Minutes into the Future"

In this particular case, Matheson employed the same technique: most of the readers of the story in the 1950s could reasonably expect to be alive in the 1970s, so the society could be anticipated to be familiar but yet there's time for a big event such as an unspecified world war (or at least a major one) to take place to make the backdrop.

Answer 2

By 1954 the cold war was already in full swing. The US had already begun the nuclear arms race and the soviet union was following quickly - their first A-bomb detonated 1949. 1952 the US detonated the first H-Bomb. The world was taken by surprise when the Soviets did the same 1953.

So, a keen observer, as Science Fiction authors usually are, would see two opposing super powers, both creating a weapon unlike anything created before - based on e.g. the gap between WW1 and WW2 and the progress the two powers were making one could make an educated guess when things might escalate and end up somewhere in the 60ies, 70ies.

Incidentally, this was a pretty good guess, as people were deeply worried at that time about a nuclear war with some pretty close situations (from Cuba Crisis 1962 up to Petrow’s keen judgement 1983).

Answer 3

I suggest that the distance between the end of WW1 (1918) and the beginning of WW2 (1939) being roughly 20 years had something to do with it -- 20 years is long enough for something that was hard for many to believe would happen happening anyway.

Many 1960s science fiction shows were set in the 1980s (like Voyage to the Bottom of the Sea) or 1990 (Lost in Space and Space 1999). I think brilliant was giving Star Trek hundreds of years to make the truly astronomical advances in technology more plausible.

Note that after the 1969 Moon Landing, grade school text books had humans on Mars within less than a decade and that did not seem crazy for we went from powered flight in wooden planes to the Moon in just over half a century. But technological problems I think are often much harder than they seem. If you asked someone, look, we got men on the moon and sent unmanned spacecraft to not just Mars but before that Venus, how hard could it be to send a manned ship to Mars? even a sophisticated person (like von Braun) would have been optimistic.