Hm. Well, that's all of the published Jake Grafton novels; now we can move onto something else.
America is the story that revolves around stolen submarines, plots to destroy the United States' economy through electromagnetic Tomahawk missiles, a Star Wars -type space defence missile shield. Improbably, ridiculous, decent pulp.
Liberty was written after the attacks of September 11th. Like a number of other books, it's about bad guys--this time terrorists, instead of agents of other states--trying to get a hold of WMDs, in this case Russian nuclear warheads. Jake has to find all four before they're exploded. Naturally, life's complicated. He decides to retire at the end of the book--two or three books late, in my opinion, but hey. Decent fun, nothing special.