True, but the Iranians are not that stupid. They would be attacking a sovereign nation with all the consequences that that would have. In the long term the Iranians would be the ultimate losers in any such scenario. Their military would be simply reduced in an attrition war and they no it. First to go would be their navy and air force assets and their air defence system.
The Iranians are struggling intensley to keep what mil assets operational as they are. If the current regime in Iran wants to survive then the last thing they would do is invade any part of Iraq
IMHO, they would want us to attack so we use nukes, so that there can be a nuclear retaliation. even if we are just using tactical nukes.