1) I am in America
2) I am a noder
3) America is a place where noders are
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4) Therefore, if you are in America, then you are a noder.

In this case, all the premises are true, but the conclusion doesn't follow. If the conclusion did follow, this would be not only a valid argument, but a sound one.

In*val"id (?), a. [Pref. in- not + valid: cf. F. invalide, L. invalidus infirm, weak. Cf. Invalid infirm.]

1.

Of no force, weight, or cogency; not valid; weak.

2. Law

Having no force, effect, or efficacy; void; null; as, an invalid contract or agreement.

© Webster 1913.

In"va*lid See Invalid null.]

A person who is weak and infirm; one who is disabled for active service; especially, one in chronic ill health.

© Webster 1913.

In"va*lid (?), a. [See Invalid, n.]

Not well; feeble; infirm; sickly; as, he had an invalid daughter.

© Webster 1913.

In"va*lid, v. t.

1.

To make or render invalid or infirm.

Dickens.

2.

To classify or enroll as an invalid.

Peace coming, he was invalided on half pay. Carlyle.

© Webster 1913.