Soon he'll be claiming that you shouldn't be in Social Security because Lisa Simpson can hack the website and steal your identity.
The argument is real... unfortunately Cotton has the wrong set of facts buttressing it. These days anyone can hack a machine with the right equipment, so instead of going after Obamacare for being "hackable' maybe they should go after the hackers and/or any countries sponsoring them? (assuming the Tea Party isn't sponsoring anti-Obamacare hackathons themselves- of course)
I don't think it's very feasible doing that, but you know, generally, if you are in a war against hackers, you almost always are certain to lose, if you aren't ahead of the curve. The greatest problem, really, is not Obamacare, but the fact hacking is quite easier than you and I wish it was. To use that fact to build an argument against Obamacare, supporting repeal, makes it baloney.