Of course can and will the state force you to reveal at least one adress. But how will they force you to give them all of your adresses you're dealing with?
If theres a way to force you in compliance a state will do so. But I don't see how in this case.
record your internet activity, make the use of strong encryption to hide activity a crime, secure a warrant for your home/computer/safetydeposit boxes, make penalty for the refusal to provide key to encrypted files/partitions worse than the underlying crime (i.e. it is 5 years in prison and forfeiture of the value of the address for failing to reveal it, but 30 years in prison and forfeiture of all assets for not providing the passphrase), use
enhanced interrogation techniques (a euphemism for torture make no mistake about it), employ the use of drugs to compel you to testify against yourself, deem your non-compliance the actions of an enemy of the state and seize all property and assets (truthful or not), keep you under surveillance, compel your neighbors, business associates, family members to testify against you.
Worst case scenario deem you a national security risk and assasinate your without due process or trial. While that might get them your private keys it may make other subjects less likely to hide things from the govt for fear thus future "misunderstandings" might result in their extermination.
Not saying the state will do so however the state makes the rules. The idea that there is a limit to what the state "can" do is just laughable. Governments have murdered more of their own people (people they exist to protect) than any criminal, terrorist or foreign enemy ever has.
U.S.S.R. (1917-1987) 61,911,000
Communist China (1949-1987) 35,236,000
Nazi Germany (1933-1945) 20,946,000
Nationalist (or Kuomintang) China (1928-1949) 10,076,000
Japan (1936-1945) 5,964,000
Cambodia (1975-1979) 2,035,000
Turkey (1909-1918) 1,883,000
Vietnam (1945-1987) 1,678,000
North Korea (1948-1987) 1,663,000
Poland (1945-1948) 1,585,000
Pakistan (1958-1987) 1,503,000
Mexico (1900-1920) 1,417,000
Yugoslavia (1944-1987) 1,072,000
Czarist Russia (1900-1917) 1,066,000
Note these aren't govt killing "others" (i.e. the United State's extermination of Native Americans, or the number of humans who died under slavery) there are the govt killing "self" and just in the last century. Exact numbers may not be known but a pretty conservative number is that ~200 million "citizens" were killed by their own government just in the prior century.
This needs to be further up. Just because the place we live isn't called "The Soviet Union" does not mean that you won't see the same tactics being used. Governments today already are more intrusive than the Soviet Union -- they're just not as openly violent...
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