The infrastructure of the highways in the US is suffering and it is getting very old.

Fixing it requires humongous amounts of money.

Some states are (considering) leasing the highways to the private sector so that they take care of it.

The private sector can toll people using those road as much as they like... maybe affected by politicians?

The private sector takes the risk for new highways - and that relieves the government from worrying about it... However, some governments have contracts that will increase their cut if the highway proves to be more profitable!

Some states got into very long leases (75 year lease/99 year lease) that they regret getting into...

Europe has been privatizing its highways forever -and in fact some of the highways in the States are operated by European companies.

A highway in California is charging $1 a mile in the express lane... very expensive, but well worth it so that the State can pay its expenses!