UnScramble this Word: h i f a t?

Questions

In 43BC The Roman politician, ---------- , is slain. ?

In 1917 USA declares ---------- on the Prussian-Hungarian forces, joining World War One on the side of the Allies. ?

In 1941 Japanese bomb ---------- Harbour. The USA join Allies in fighting the Axis forces soon after. ?

In 1971 (USA) Rube---------- , inventor and cartoonist, dies. ?

In 1934 Weekly airmail route starts between ---------- and the United Kingdom. ?