Libertarians (capital "L") are so varied, and so freedom oriented, that they are essentially dysfunctional as a party.
Some are isolationists. There is no doubt about that.
Others believe that defense of the country is the first and primary duty of government...the last governmental function to cut or wind down, in the pecking order of wasteful government programs. The next most important is justice. All other functions are discretionary.
Iran has been fighting a low grade war against us since 1979. Even libertarians have to pull their heads out of the sand to breathe every so often, and may notice the reality of the threat that Iran is. I don't think I would have ordered the attack on Iran, but I can't say it is bad that Trump did. You can't deny that if Trump's attack works, the entire world, including Americans and the Iranian people, will be much, much better off.
..
I'm curious, are you a neocon because you agree with me that we should help Ukraine in their fight against Russia?