simple states choosing function

[quickstopman]

i have no idea how to do this is JS but i think its possible

i want to make it so when a user selects his country, if its the US it shows the states, but if it isn't the US then it doesn't show the states.

here is what i think might work!

<script>
function us() {
var us = true
if (document.getElementById('countrys').value="United States") {
document.getElementById('states').visiblilty="visible";
} else {
document.getElementById('states').visibility="hidden";
}
}
</script>

<select id="contries" onSelect="us()">
<option>
United States
</option>
<option>
Canada
</option>
</select>
<select id="states">
<option>
New Jersey
</option>
</select>

any ideas??

thanks guys