<html>
<body>
<script>
function launch() {
var target = document.getElementById("target");
var sneak = document.getElementById("sneakattack");
var proto = document.createElement("div");
if (sneak.checked) {
proto.innerText = "Comrades, have a nice day!";
} else {
proto.innerText = "Missiles launched against " + target.value;
}
document.getElementById("protocol").appendChild(proto);
}
</script>
<form id="control">
<input type="text" id="target">
<input type="checkbox" id="sneakattack">
<button type="button" onClick="launch()">Launch the missiles!</button>
</form>
<div id="protocol"></div>
</body>
</html>