> Because if an isotope emits high radiation, it will "burn out" relatively fast

> but I feel educational today...

To help people get intuition about this remember that energy is conserved. Radiation can come in multiple forms: alpha (2 protons and 2 neutrons), beta (electron or positron), or gamma (high energy "light"). At each decay even the original atom MUST lose energy, and thus, mass (thanks Einstein!).

Alpha is pretty common (how Uranium-238 decays into Thorium-234, in 4.4e9 years, releasing 4.2 MeV of energy[0]). But also note that this is large and that's why it can be stopped pretty easily (unless the MeV is very high).

Beta decay is a bit trickier because it can be either a positron or electron, but the process is quite similar. In both alpha and beta decay there's a clear mass being ejected from the atom (and along with it, energy). An example of beta decay is when Thorium-234 decays into Protactinium-234m (m for "metastable") in 24.1 days but with only 0.27MeV (you can tell here thought that this decay releases more energy over time, despite being a lower amount of energy released per decay event). Protactinium-234m then has a VERY short half-life of 1.16 minutes releasing 2.27MeV per event, turning into Protactinium-234, which also has a short half-life of 6.7 hrs, giving off 2.2 MeV of beta- (electron) decay, turning into Uranium-234, which has a long half-life of 2.45e5 years.

I think this last example is where people get confused, because we went from Uranium to Uranium, right? But the numbers are important! Uranium-238 to Uranium-234! Those are the number of neutrons in each atom. Uranium-234 is much more stable.

(I need to also note that there are some long lived products with high energies, but this is far more complicated than we have time for in this already long comment. We'd have to also discuss biological half-lives if we're going to talk about that. And someone will mention stuff about boars and mushrooms, and not understand)

The other confusing part is waste and composition of waste[1]. It's important to note that 90% of waste is "low level", which are things like clothing or tools, and only contain 1% of the total radiation in waste. This stuff is readily disposed of, and the truth here is that were this to all get lost, there would be no real serious danger posed to any{one,thing}. We like to be on the safe side with nuclear, and for good reason (this is again, complicated). But the AMOUNT of waste is __VERY__ little

> On average, the waste from a reactor supplying a person’s electricity needs for a year would be about the size of a brick. Only 5 grams of this is high-level waste – about the same weight as a sheet of paper.

And,

> Unlike any other energy generating industry, the nuclear sector takes full responsibility for all of its waste.

So this needs to be remembered when comparing competing energies. This is a common misconception when comparing and people without actual domain expertise here naively look at data and don't understand the assumptions of that data (I'm looking at us, HN...). And it is more complicated than just comparing the full waste generation from solar vs nuclear (as a far too common example. Which these technologies don't compete!)

So TLDR:

The decay can be simply thought of as "high energy, short lived" while the rest is actually incredibly complicated and exceptional levels of nuance are required for actually making good comparisons. This last part isn't isolated to nuclear technologies and is a common logic failure of many internet warriors.

TTLDR: shit is complicated, don't talk about complicated stuff if you're passion doesn't align with your efforts to educate yourself and understand the nuance.

[0] https://en.wikipedia.org/wiki/Decay_chain#Uranium_series

[1] https://world-nuclear.org/nuclear-essentials/what-is-nuclear...