Would you possibly be suggesting that the word "libertarian" existed before the word "liberal", or that "libertarianism" existed before "liberalism"?
I am well aware of the differences between liberalism and libertarianism and they aren't even close in their root foundation. Liberalism is based on a philosophy of the commonwealth of the whole, while libertarianism is based on the concept of the individual. In fact, libertarianism would be more correctly called "individualism" .. but I guess that didn't have the same ring to it and gave away its real core belief. It is in fact, a bastardization of the word "liberty" as it has no thought for the liberty of others or the commomwealth of the nation.
The core values of liberalism and libertarianism don't exist on the same planet. The libertarian would argue FOR chid labor. After all, it is a child's right to work without "force" from the government imposing restrictions, and you can depend on "the market" to do the right thing. Liberals would find such thought demonic. It's a belief in "moral" capitalism, which have never existed and demonstrates no understanding of capitalism. We can thank liberalism and the struggles of workers for the abolition of child labor, not the "wisdom" of the free market, which thrives off of cheap labor, including children.
With all due respect, libertarianism exists in an ahistorical bubble of myopic whimsical beliefs, devoid of any memory or knowledge of a long train of abuses by the free market that liberalism and social activism worked to correct. It's a philosophy devoid of any socio-ethical understandings and which bends over and drops its pants to unfettered capitalism.
Perhaps you should read Howard Zinn's "The People's History of the United States" or the writings of Einstein on socio-ethical responsibility.
Nor do I think you know Tom Paine as well as you think you do. Paine championed worker's rights, CHAMPIONED SOCIAL SECURITY, fought for the abolition of slavery and racial equality, campaigned for women's equality, CHAMPIONED PUBLIC EMPLOYMENT, campaigned against big businessn, and a host of other social reforms. In other words, he had a socio-ethical understanding of society which is absent from the libertarian mind. Perhaps you should read his "Rights of Man" before you go off stating his positions.
I've read Zinn's The People's History and that is a must-read. I've also read a lot of Paine (i have his collected works, including of course, the rights of man, in the Library of America edition), but I've never read Einstein. I will have to do that, that sounds very interesting. There is a very well-reviewed new biography of him out too. Now that you mention him in this context, maybe I will pick that up too.