I won't nationalize your assets in my country if you don't nationalize my assets in your country.
I will ban your books if you ban mine.
"I will x if you will also x" makes you reactionary and gives agency to someone else to act on your behalf.
> and gives agency to someone else to act on your behalf
Relinquishing control is a very effective negotiation tactic. If you can credibly lose agency in a given situation - precommit yourself to a course of action - this means the other party has all the control and all the responsibility. If, given your pre-committed response, one choice is bad for your opponent, they're essentially forced by you to take another one.
Thomas Schelling wrote a whole book ("The Strategy of Conflict") about such scenarios.
A toy example (I think it's even from the book): imagine we're both in cars, driving towards each other and playing chicken. Whoever veers off to avoid collision first loses. If you want to win for sure, all you have to do is to rip out your steering wheel and throw it out of the window - if I see that, my choices are suddenly reduced to "lose the game, or we both die".
A real example is automated retaliatory strike systems that both sides of the Cold War worked on - strenghtening deterrence by ensuring a retaliatory strike will happen even if humans in charge change their minds.
This is true to an extent, but I find it unpersuasive. Because it’s basically my main negotiating and parenting technique. I don’t bluff well or frequently. I prefer to lay out the options ahead of time (because I’ve already thought them through) so I can let the other party make an informed decision.
“I will buy this widget for $X. Anything more than that and I will use your competitor / build it in-house.”
“If you clean your room, we’ll get ice cream. Otherwise, no video games today.”
“If you drop a nuclear bomb we will drop our nuclear bombs.”
The catch is that you have to mean it. Which is why I don’t see any real value in bluffing in long-term relationships. We’ve all seen those parents who tell their kids “If you don’t stop doing X right now then Y” and everyone knows (especially the kid) that there will be no follow through.
But predetermining your response doesn’t give away your agency. It’s simply stating in advance how you will respond to others agency in an effort to let them make an informed decision.
Suppose hypothetically, that the EU banned imports of Australian wine, why would it be “reactionary” for Australia to respond in kind by banning imports of EU wine?
EU would ban Aussie wine only if the benefits overweights straight reciprocation.
So Australia stating it will ban EU wines as a reaction just let’s the EU validate it’s worth it. If it’s not, no ban is set and nobody gets hurt. If it is, both bans are set but the EU comes out better if their calculations are right.