the.com/trial balloon

An idea you float publicly so someone else can shoot it down for you.

means A proposal or announcement deliberately released to gauge public reaction before committing to it for real.

from Literally a small balloon sent up to test wind direction and speed before launching a real one — a practice in ballooning and weather observation. By the early 20th century, the phrase had drifted into politics and journalism to describe floating an idea to see which way public opinion blows before fully committing.

origin
literally weather balloons tested before manned flights
political use
leak a policy, measure outrage, deny it existed
key feature
deniability built in from the start
tell
vague sourcing, anonymous officials, no real commitment
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