The U.S. has no property taxes in that sense (a tax on all owned property, more commonly called a "wealth tax"). Some states have a tax called a "property tax", but it applies only to land and buildings ("real property"), not to other kinds of property such as stocks, baseball cards, gold, bitcoin, bank accounts, paintings, etc.
In many locations the taxes on vehicles come in the form of a separate excise tax on 'value' given to the vehicle based on its original value and age, this tax is administered at the City level where I live in Massachusetts.
Are there locations in the US where the general property tax is applied itself to vehicles? Or were you simply stating that things other than land and buildings could be taxed, and not that the property tax applies to them?
Property tax is subtle, but here's what it looks like in a nutshell:
The article talks about treating it as property vs currency. If the IRS chose currency, all realized[1] gains/losses on BTC get treated as ordinary income (lumped in with salary/wages) and get taxed at income rates. For most bitcoiners this would be around 15% if your salary is under $75,000/yr[2] and around 30% if more.
If the IRS chose property your tax rate depends on how long you held it (and some other things, it's subtle. But mostly how long you held it). If you bought and sold within a year it gets pushed into ordinary income as shown above. If you held it for over a year you pay 15%[3] on the gain.
Note that property transactions still kick into gear even if you didn't cash out into dollars. If you bought in at $10/BTC, get a new lambo[4] at $1000/BTC you pay the property tax (capital gains) on the bitcoin gain.
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[1] Gains from when you cash out (cash out price - buy in price)
[2] Upper middle class in most of the country, excepting the very big and trendy urban centers
[3] If you sold those collectible bit coins you'd probably pay 28% on the gain.
[4] So there's this guy, and he's got a brand new Lamborghini and he wants to put a mezuzah in it...
If I understand this correctly this can be a huge blow for Bitcoin users in the US