...because 1970 marked the first time since the Great Depression that a well educated man(almost all engineers in 1970 were men), with a good position in his company, could lose his job through no fault of his own. This was part of the great "engineering recession" that lasted from 1970-1973 and was mainly caused by the fact that the government needed its money for bullets in the Vietnam War, we had made it to the moon in 1969, and the government had no money for designing fancy expensive defense gadgets, in particular aerospace gadgets. Thus aerospace engineers, the kind of engineer George Kennedy plays in this film, got hit particularly hard. The ones who were over 40 had the same problem those over 40 hit by the Great Recession starting in 2008 had - nobody wants to hire you for a professional position because you are too old. What they tell you is "you are not a good fit". Or "we'll call you if something comes up".
George Kennedy plays the out of work aerospace engineer, and as the film opens he is cleaning out his spacious office - he obviously had a good career - as he has been laid off. Vera Miles plays the supportive wife. Even though his job search yields nothing - as does those of his engineer friends - he insists on throwing the big Fourth of July barbecue bash that the family has every year. It really is not about putting on a show for the friends and family as it is a way of stating that his self worth is still the same as it has always been.
I remember a particularly poignant moment is when Kennedy is driving down the street and the engineer friend he had that kept saying "prosperity is just around the corner" is spotted by Kennedy's character pumping gas back in the days when people were actually employed to do that for customers. Kennedy has a look on his face that says "Is that going to be me?".
I haven't seen this film for 45 years when it first ran, and it has never been on DVD and likely never will be. It was on VHS at one time, but is out of print. It will never be on DVD because being booted by your company after decades of service - if you last that long - for no reason has become the "new normal". Nobody remembers that for the first 25 years after WWII anybody who wanted a job could find and keep a job.
Why do I remember this so well? Because I am an engineer and my dad was an engineer. I remember every Friday as a teenager in the early 1970's dreading him coming home and saying he had lost his job. It was a real possibility. It happened to one of his carpoolers and it happened to my uncle with a catastrophic impact to their respective finances.