Really, you are left wing on social issues and immigration and national defense?
Libertarianism is not Left Wing on social issues.
They believe in minding own business in the world. Strong national defense. No alliances, no defending of multinationals overseas. No sacrifice of American soldiers for foreign interests. I support all of these.
Social issues like homosexual marriage. They think that people can do what they want in the social sphere. But also, libertarians are free NOT to associate or be with people they do not like or agree with. Libertarians do not buy the public school system to which so many conservatives use and lose their children. They can run their companies as they see fit working with whomever they want.
On abortion: people do as they see fit, but a libertarian does not have to pay for the abortion of others.
On drugs: libertarians believe in an open drug policy. So do I. Work in the field. If people want drugs let them buy them at the drug store. Caveat: No publicly funded healthcare or services for folks testing positive for
drugs. If the privates like the Sallies or Catholic Charities want to step up with donations, great, but people can destroy themselves on their own dime.