But we will remember.

[sitifan]

"The United Kingdom, our once Great Ally, maybe the Greatest of them all, is finally giving serious thought to sending two aircraft carriers to the Middle East," Trump wrote on Truth Social on Saturday. "That's OK, Prime Minister Starmer, we don't need them any longer - But we will remember.
"We don't need people that join Wars after we've already won!"
Source: https://www.bbc.com/news/articles/c9dn3j04lydo

What is the object of remember?

 

[Skrej]

It's being used intransitively here so there isn't an object. However it's referring to the actions of the UK, which are what will be remembered.

 

[emsr2d2]

I'd say that it specifically means they'll remember Starmer's actions.