fresh nginx install won't start: lacks permission to bind to port 80

This is a new one on me after maybe a dozen or so NGINX installs on Ubuntu 18.04. This happened on a Windows 10 machine using the Windows Subsystem for Linux, running Ubuntu 18.04 freshly installed. Nothing else has been installed.

Here's what I get:

doctor@Lenovo-Ideapad2:~$ sudo service nginx start
nginx: [emerg] bind() to 0.0.0.0:80 failed (13: Permission denied)
doctor@Lenovo-Ideapad2:~$ sudo nginx -t
nginx: the configuration file /etc/nginx/nginx.conf syntax is ok
nginx: [emerg] bind() to 0.0.0.0:80 failed (13: Permission denied)
nginx: configuration file /etc/nginx/nginx.conf test failed

In Windows right after this happened I checked Port 80:

C:\WINDOWS\system32>netstat -aon | findstr :80
TCP 0.0.0.0:80 0.0.0.0:0 LISTENING 4
TCP 192.168.1.119:52240 72.21.91.29:80 CLOSE_WAIT 12636
TCP [::]:80 [::]:0 LISTENING 4
TCP [2604:6000:1513:49d4:75ef:2fb6:7dba:daaf]:52472 [2001:4998:60:800::1105]:443 ESTABLISHED 13304


Why is this happening?

Thanks.