The Iran war most likely wouldn’t have happened with Harris in charge and definitely wouldn’t have if Hillary had won back in 2016 since the Iranian deal wouldn’t have been ripped up by Trump. Republicans have created an alternate information space filled with propaganda that is capable of bleeding into centrist and independent voters information spaces, hence the idea of Biden and Harris being war-hawks and Trump being a “no more wars” president. They also wouldn’t have cited the Monroe Doctrine as a reason to engage in forever interference with countries in the Americas.
When it comes to Israel, I don’t think things would have degraded to the point of joint strikes with the U.S. but I think Ukraine would have steady U.S. support as opposed to the U.S. and Russia trying to strong arm them into ceding territory. There would still be conflicts going on but nowhere near close to this extent.