Ivanka Trump was soaking up the magic at Disneyland Paris … just as her father, President Donald Trump, threatened to kill off Iran's "whole civilization."

Ivanka was seen Tuesday with her kiddos, roaming the French amusement park ... and made a stop at "Crush's Coaster" -- a spinning "Finding Nemo" themed roller coaster.

Check out the video ... the group's grinning ear-to-ear as they exit the ride -- looking ready to take on the rest of the park.

An eyewitness tells us the crew had plenty of security around them ... with at least one security guard posted outside the coaster, earpiece in, waiting for them to finish.

Clearly, Ivanka and co. are thrill-seekers ... we're told they also hit the "Tower of Terror" -- a drop ride that plunges riders 13 stories.

Needless to say ... it's a STARK contrast from what was unfolding back home -- with Donald Trump weighing the total destruction of Iran. Her hubby, Jared Kushner, has also been a key negotiator in the Iran conflict.

However, the Disney getaway is in line with Ivanka's new approach to White House politics. She's rarely at her father's events, lately ... as she's, at least publicly, distanced herself from presidential politics during his 2nd term.

Full transparency ... our footage of Ivanka was taken about 30 minutes after Trump fired off his bombastic threat on Truth Social.

Ultimately ... Trump says he hashed out a deal with Iran -- agreeing to a 2-week ceasefire ... just before a self-imposed deadline of bombing the country back to the "stone ages."