Coinbase is a great company, unfortunately The US is very corrupt and coinbase will roll over to their demands at a whim.
By storing your Bitcoins at coinbase the best outcome you can hope for is the government stealing 15% of them.
Do not store your Bitcoins in coinbase, but in a paperwalet or hardware wallet-
Read this -
https://bitcointalk.org/index.php?topic=858604.0and this
https://bitcointalk.org/index.php?topic=899253.0For more information.
This is not secure because all the IRS or an ex-wife has to have knowledge of is mere suspicion which can and will happen
with normal reporting or an audit. Remove your bitcoin and transfer them a few times to other new addresses before
securing them with one of the options above.
Personally, I am very sloppy with my bitcoin and keep losing it, forgetting my passwords, and giving it away.