Lukaku has returned on-loan after a season away with Chelsea.
“I am not surprised he returned to Milan. Actually, I welcome him back to his real home," Klinsmann told La Gazzetta dello Sport.
“However, never take anything for granted, there is a bit of risk. This is a different Inter, they played differently last season with other strikers such as Dzeko and Correa.
“Now, it will be important to understand whether Romelu will make himself available, starting from scratch with a new system. I have no doubts it will happen, he is back to being happy again."