@munin That's a great way to frame and look at it.
That means tolerance is not something somebody has or not, but exists between people. A form of mutual relation that both (or all) parties necessarily need to contribute too.
Like a dialogue. Communication can be one-way, monologues can be exchanged. But when one stops contributing to a dialogue, there is no dialogue anymore.
So if one party ceases to uphold the shared value of tolerance, there is no tolerance present for anyone anymore.