Push selection to another array for storage

Hi wrote probably my first JavaScript code, I have a slight problem with it.

I want to randomly select a country and then the random selection should be added to the array called sel_count_arr

so if you push the button 5 times then five random countries should be pushed to the sel_count_arr

the selecting random countries part is working, but pushing the selection to the empty arrey is not.

can someone help me to figure this out?

<button type="button" onclick="document.getElementById('countries').innerHTML = random_countries(country_list)">Click for random country</button>
<p id="countries"> </p>

<h3>Selected countries:</h3>
<p id="selected_countries"></p>

<script>
function random_countries(country_list)
{
 return country_list[Math.floor(Math.random()*country_list.length)];
}
var country_list = ["Afghanistan","Albania","Algeria","Andorra","Angola","Anguilla","Antigua &amp; Barbuda","Argentina","Armenia","Aruba","Australia","Austria","Azerbaijan","Bahamas"
        ,"Bahrain","Bangladesh","Barbados","Belarus","Belgium","Belize","Benin","Bermuda","Bhutan","Bolivia","Bosnia &amp; Herzegovina","Botswana","Brazil","British Virgin Islands"
        ,"Brunei","Bulgaria","Burkina Faso","Burundi","Cambodia","Cameroon","Canada","Cape Verde","Cayman Islands","Chad","Chile","China","Colombia","Congo","Cook Islands","Costa Rica"
        ,"Cote D Ivoire","Croatia","Cruise Ship","Cuba","Cyprus","Czech Republic","Denmark","Djibouti","Dominica","Dominican Republic","Ecuador","Egypt","El Salvador","Equatorial Guinea"
        ,"Estonia","Ethiopia","Falkland Islands","Faroe Islands","Fiji","Finland","France","French Polynesia","French West Indies","Gabon","Gambia","Georgia","Germany","Ghana"
        ,"Gibraltar","Greece","Greenland","Grenada","Guam","Guatemala","Guernsey","Guinea","Guinea Bissau","Guyana","Haiti","Honduras","Hong Kong","Hungary","Iceland","India"
        ,"Indonesia","Iran","Iraq","Ireland","Isle of Man","Israel","Italy","Jamaica","Japan","Jersey","Jordan","Kazakhstan","Kenya","Kuwait","Kyrgyz Republic","Laos","Latvia"
        ,"Lebanon","Lesotho","Liberia","Libya","Liechtenstein","Lithuania","Luxembourg","Macau","Macedonia","Madagascar","Malawi","Malaysia","Maldives","Mali","Malta","Mauritania"
        ,"Mauritius","Mexico","Moldova","Monaco","Mongolia","Montenegro","Montserrat","Morocco","Mozambique","Namibia","Nepal","Netherlands","Netherlands Antilles","New Caledonia"
        ,"New Zealand","Nicaragua","Niger","Nigeria","Norway","Oman","Pakistan","Palestine","Panama","Papua New Guinea","Paraguay","Peru","Philippines","Poland","Portugal"
        ,"Puerto Rico","Qatar","Reunion","Romania","Russia","Rwanda","Saint Pierre &amp; Miquelon","Samoa","San Marino","Satellite","Saudi Arabia","Senegal","Serbia","Seychelles"
        ,"Sierra Leone","Singapore","Slovakia","Slovenia","South Africa","South Korea","Spain","Sri Lanka","St Kitts &amp; Nevis","St Lucia","St Vincent","St. Lucia","Sudan"
        ,"Suriname","Swaziland","Sweden","Switzerland","Syria","Taiwan","Tajikistan","Tanzania","Thailand","Timor L'Este","Togo","Tonga","Trinidad &amp; Tobago","Tunisia"
        ,"Turkey","Turkmenistan","Turks &amp; Caicos","Uganda","Ukraine","United Arab Emirates","United Kingdom","United States","United States Minor Outlying Islands","Uruguay"
        ,"Uzbekistan","Venezuela","Vietnam","Virgin Islands (US)","Yemen","Zambia","Zimbabwe"];

var sel_count_arr = [];

document.getElementById("selected_countries").innerHTML = sel_count_arr.push(random_countries(country_list));

</script>