if you are paying a million dollars a year to take out whomever with you when you bite the big one... would you really care about dropping a nuke in the middle of the city? not like you are going to be living here...
You might not, but trust me, no corp is going to want to be known for dropping nukes at the drop of a hat, even if said hat is on the head of a contractee. Basically, let's imagine our contractee (with a nuke contract) bites it while inside some Ares complex in Seattle.
Deathwagon goes in, and drops a small nuke, maybe... 17 kT or so.
This destroys everything in say... 1.5 miles radius (probably more, but I'm assuming fairly hardened non-military targets), in particular including said Ares complex. So what? Well, for one thing, Ares will be mightly pissed. And they'll want their money back, somehow. Now, even if DeathWagon somehow could avoid being legally responsible for the damages, Ares is big, mean and
international enough to go after Deathwagon. Chance are that most of the other 'Big Ten' would've lost substantial valuables too, and wouldn't hinder Ares, maybe even aid them.
Then ofcourse there are the secondary targets, some... 17,000 of them in the initial blast, and upwards of a million if we include radiation based deaths. And extra territoriality gets iffy in murder cases. Indeed, ye olde Us went to war for far less.
Losing the money from other contractees in the blast would not be the greatest of your worries either. Contracts would bind you to nuke the area of their deaths too. Soon, you'd have scorched the entirety of Seattle off the map, along with most of your costumer sources.
Oh, and mind you, you
might be able to buy a functional nuke for 1 mio nuyen (though I doubt it, seller's market), but that wouldn't include any ICBMs, trust me on that.