1)  A nation must have a navy to form a large empire.
          large empire implies navy
          An empire is a sufficient condition for a navy.
          A navy is a necessary condition for an empire.
Falsification: An empire without a navy.

2)  Democratic nations don't fight each other.
          Two nations are democratic implies do not fight.
          NOT that if two nations do not fight then they are
     democratic
          Democratic nations are sufficient for not fights.
 No fights are necessary for nations to be democratic.
Falsification:  Two democracies fight each other.

3)  Power transition theorists maintain that wars only occur when
there is power parity.
 war implies power parity.
 Power parity is a necessary condition for war.
 War is a sufficient condition for power parity.
Falsification:  War without power parity.

4)  US Presidents are more hawkish in their first term than their
second term.
 2nd term implies more dovish behavior.
          2nd term is a sufficient condition for less aggressive
     behavior
Falsification:  A President that is more hawkish in his second
term.

5)  High investment results in economic growth.
 high investment implies economic growth.
          NOT economic growth implies high investment, the growth
     could occur for other reasons.
          High investment is a sufficient condition for economic
     growth.
Falsification: High investment but no growth.

6)  I do not want what I have not got.  (S. O'Connor)
 Not having implies not wanting.
          Not wanting is a necessary condition for not wanting.
Falsification:  Wanting something that I do not have.

7)  Unpopular governments are more likely to become involved in
wars than popular ones.
          Increased unpopularity implies  increased probability of war.
          Unpopularity is a sufficient condition for an increased
     probability of war.
Falsification:  Unpopular governments involved in less wars than
popular ones.  This is a probabilistic statement so it is not
falsified by a single event.

8)  In a bipolar system competing alliances resemble one another.
          Bipolar system implies  alliance resemble each other.
          Alliances resembling each other is a necessary condition for
     a bipolar system.
Falsification: A bipolar system with alliances that do not
resemble each other.

9)  A power vacuum leads to war.
          Power vacuum implies war
          A power vacuum is a sufficient condition for war.
Falsification:  A power vacuum that does not lead to war.  NOT a
war without a power vacuum.

10)  A nation only intervenes in an ongoing war if it is allied
with one of the belligerents.
          Intervention implies allied to one side.
          Being allied to a combatant is necessary but not sufficient
     for intervention.
Falsification:  A non-allied nation intervenes.