The first season was great but not the second season because political issues seem like games, especially the part that Moss tries to persuade President Han and Chairman Kim to sign on the agreement...
And, Hannah Wells's investigation should be this show's main storyline because Hannah is actually the one who promotes the development of the plot, even though the situation happens on Tom Kirkman and the White House.
I would say:
First season: 4.5/5
Second season: 2/5