Assertion not visible in the console in SOAP UI 5.5.0 opensource version

Assertions are available for the test steps only.

You need to right click on project -> Test Suite -> Test Case -> Test step.

As nmrao said, the part that is shown in the picture is the Soap definition - you can't put assertions on the definition itself.

 

The assertions can be placed on test steps. In your case I see that you have TESTSUITE1 -> CapitalCity TestCase -> CapitalCity.

 

Cheers!