I'm not entirely sure the Cold War ever ended, we just don't use that phrase anymore so that people don't think about it or know how to refer to the arms race of continual production of nuclear weaponry around the world.
For the purposes of mutually assured destruction, you only need to be able to destroy civilization once.
With respect to whether a war has ended or not, I'd rather look at the annual defense budget.
The US defense budget, as a fraction of GDP, has spiked four times, to 12%, 22%, 41%, and 15% for Civil War (does not include CSA spending), WW1, WW2, and Korean War.
Since then, the Vietnam War steadily consumed about 10% of GDP for several years. After it was declared over, spending dropped to 5.5% until the Cold War started. Then it popped back up to almost 7% in 1986 before dropping down to 3.5% in 2001. Then it went up to 5.7% in 2010 before starting to drop again. We're now at about 3.3% again.
Prior to WW2, peacetime defense spending was a consistent low level of 1% to 2% of GDP. The US has never reached such low levels of military spending since.
But the Cold War is a clearly visible bump in the chart around 1986. Similarly, the War on Terror seems to have peaked in 2010. The Cold War, specifically, ended in 2001. But the US has never gone back down to a peacetime economy since the end of WW2.
With my tinfoil hat on, the numbers almost look like the lizard-people are titrating to find the optimal intensity of continual war, to maximize their revenues from military spending.
